Park Predators - The Ride

Episode Date: September 2, 2025

On a quiet mountain in eastern Tennessee, three men ride off on all-terrain vehicles for an evening of exploring, fishing, and swimming but never return. When foul play is revealed, what seemed like a straightforward murder mystery turns into a bizarre puzzle that local law enforcement spend nearly a decade trying to untangle. This is the story of the July 1988 Signal Mountain murders.View source material and photos for this episode at: parkpredators.com/the-ride Park Predators is an audiochuck production. Connect with us on social media:Instagram: @parkpredators | @audiochuckTwitter: @ParkPredators | @audiochuckFacebook: /ParkPredators  | /audiochuckllcTikTok:  @audiochuck

Hi, park enthusiasts. I'm your host, Delia Diambra. And the case I'm going to tell you about today is one that I've had my eye on for a long time. It's the infamous triple murder case in Signal Mountain, Tennessee that's likely well known to residents in the eastern part of the state. This case is actually one I kicked over to crime junkie back in the summer of 2021, when the second season of Park Predators was released. Ashley and Britt covered it on their show at a high level to get their listeners geared up. for New Park Predators episodes. But I've never done my own deep dive on the story, until now. To really immerse myself in the case, I took a trip to Chattanooga, Tennessee and the town of Signal Mountain to do research and visit some of the locations associated with the crime. My husband grew up in Chattanooga, so he was more than excited to tag along with me

and help take some of the pictures and videos we've put out on social media for this episode. Something important to know about Signal Mountain is that back in 1988, when this crime occurred, it was a very tight-necked community. In many respects, it's still that way today. The town's website estimates that around 8,800 residents live there on Walden's Ridge, which peers down over downtown Chattanooga and the Tennessee River Gorge. Many locals and visitors enjoy hiking or mountain biking the town's 18 miles of trails, which connect to nearby Prentice Cooper State Forest and Shackleford Ridge Park.

In July 1988, though, it seemed every trace of recreational activity in the area came to a screeching halt when three men riding ATVs in the woods vanished, only to resurface in one of the most puzzling mysteries to ever happen in the quiet mountain town. This is Park Predators. I'm going to be able to be. After 9 o'clock at night on Saturday, July 9th, 1988, a young woman named Paula Griffith stared into the woods next to her parents' home in Signal Mountain, Tennessee. She was watching eagerly for her husband, 22-year-old Kenneth Griffith, to ride up on an ATV. A few hours earlier around 6 p.m., Kenneth, his 24-year-old friend Earl Smock, and Paula's father, Richard Mason, had left the rural property on three-wheelers, though some source of

say, four-wheelers. The men had ventured into the surrounding landscape to go for a joy ride and intended to do a little evening fishing at a scenic swimming spot known as the Blue Hole, which was about three miles north of the Mason's home. The trails leading to that destination were ones that Kenneth and Richard had ridden many times before, because Richard, his wife Martha and Paula, who was married to Kenneth, had lived on Signal Mountain for about 13 years at that point. And Kenneth was from the Chattanooga area.

He'd met Paula in high school, and not long after graduating, the couple got married. Paula told producers for the television program Bloodlands that Kenneth had never been the biggest outdoorsman, but over the course of their relationship, he'd grown close with her dad and picked up a lot of skills and knowledge about the outdoors from him. So Kenneth and Richard going out for a quick evening ride in the woods was something fairly routine for them when they were together. Earl was the only newcomer in the group. He'd grown up in Decatur, Tennessee, which is about an hour northeast of Signal Mountain. Even though he had experience riding all-terrain vehicles, he'd never traversed the specific geographic area around the Mason's property before.

But since he had Kenneth and Richard with him, he was good to go. He'd met Kenneth after enlisting in the Air Force, and the pair became good friends while stationed in the same squadron at an Air Force base in the Florida Panhandle. A few days before going out on the ATVs, Earl, Kenneth, and Paula, had traveled up from Florida to visit with her folks and have some relaxing downtime. Now, before the three men left to head out on the trails around Signal Mountain that Saturday evening, they'd packed three Diet Cokes and some beers in a cooler,

and Kenneth and Earl had put on their Air Force flight suits. Richard had also geared up, too, but in a different way. He'd wrapped a 44-caliber pistol he owned in a towel and stowed it beneath the seat of his ATV. None of the source material explains why he armed himself, but I don't believe it was because he expected to run into trouble. From everything I gathered, it appears that him bringing the gun was something that a lot of locals in that rural community did whenever they've entered into the woods.

Having firepower within reach was, I imagine, a common practice for folks who wanted to protect themselves against, say, wildlife. The terrain on Signal Mountain is remote in some places and has lots of twists and turns, are not only dangerous if you don't know what you're doing, but also serve as habitats for natural predators, like coyotes, black bears, and bobcats. So having a firearm with you isn't the worst idea if you accidentally disturb one of those animals. Anyway, as Saturday night got later and later, Kenneth, Richard, and Earl never came home. Paula and her mother Martha's

curiosity about where the guys were turned into genuine worry by the following morning, Sunday July 10th, when the men had still not returned. The previous night, Martha had tried to comfort her daughter by suggesting that maybe the trio had just decided to camp overnight at Blue Hole or maybe had been unable to navigate back safely in the dark, so they'd waited until morning. But that rationale quickly vanished when the hours ticked by on Sunday and none of the guys showed up. At that point, neither Martha nor Paula could suppress their gut feeling that something was

seriously wrong. So around 9 a.m. Martha called over to a few friends and neighbors to see if they'd spotted her husband, son-in-law, and Earl, but no one had. Sensing the situation was unusual, people who knew the Mason started a small search of their own. But after a while of doing that and getting the same results, Martha realized she needed to get law enforcement involved and dialed the Hamilton County Sheriff's Department, which is currently known as the Hamilton County Sheriff's Office, and she reported all three men missing. According to police records cited in a book about this case titled Statement of Facts, State v. Castile, an officer arrived at the Mason's home to take the missing person's report at 6.45 p.m. on Sunday night. Some information he wrote down in that

report was that 49-year-old Richard had been writing a red Honda AT and wearing a blue sleeveless cut-off work shirt, blue jeans, and a blue hat. Kenneth, who had unmistakable brown, red hair had also been on a red Honda all-terrain vehicle and was last known to be wearing his Green Air Force flight suit and a white hat with an orange tea on the front. Now, to me, just based on that unique description, it sounds like the emblem on Kenneth's hat could have been a Tennessee Volunteers baseball cap, but I'm not 100% sure. It would make sense, though, if it was that school's logo since Chattanooga is only a few hours southwest of Knoxville. When Earl was last scene, he was also in his flight suit, but he'd been riding a blue and white Honda ATV.

According to the coverage, not long after the missing person's report for the men was taken, the sheriff's department prepared to issue an alert about the men. But before they could, they got another call that wasn't immediately connected to the disappearances, but was certainly out of the norm for the Signal Mountain community. The caller was a man who claimed that shortly after 7.30 p.m. on that Sunday, along a winding mountain road named Roberts Mill Road, a man and a woman who'd pulled over to check one of their tires had flagged him down and reported

that they'd found at least two ATVs tossed down a steep embankment that was adjacent to the roadway. This ravine area was a place people would often illegally dump trash and it had all kinds of junk in it, but ATVs were definitely atypical garbage, even for that spot. So the couple who'd seen the all-terrain vehicles had felt that the discovery was unusual enough that they needed to flag someone down and get that person to drive to the nearest place

with a phone to notify law enforcement. And I know this sequence of events feels foreign to us now in the digital age, but you've got to remember this was 1988 we're talking about. Cell phones were not a thing yet, so this couple stopping another motorist to help them relay their discovery to police was the best they could do at the time. Anyway, when a deputy with the sheriff's department arrived to the bluff area that overlooked the trash dump. He peered down the slope and saw exactly what had been described to him. At least two ATVs just sitting at the bottom of the embankment, and according to police records cited in the book's statement of facts,

there were also a handful of people loitering in the area who'd remained on scene until authorities got there. Not long after the ATVs were found, two detectives with the sheriff's department arrived at Roberts Mill Road and began investigating. Those guys' names were Larry Sneed and Roy Parab. As they looked over the first ATV they came to, they immediately noticed it had what appeared to be blood on it,

and nearby was another ATV that also had traces of blood present. Neither vehicle, though, appeared to be damaged, like it had been wrecked. As they continued to work, they checked compartments on the ATVs, and beneath the seat of one of them, they discovered a 44-caliber pistol wrapped in a towel. Not long after making that discovery, they stumbled upon a third ATV further down the slope. But this one had no traces of blood on it. It was as clean as could be. According to Unsolved Mysteries, it didn't take the detectives very long to make the connection

between the three abandoned ATVs and the missing persons report for Kenneth, Richard, and Earl. By Sunday night, the two incidents had been linked, and because none of the men had been found yet, the prognosis was looking more and more like something bad had happened to them. But authorities still had a lot of investigating to do. Primarily, they needed to find the three guys and also figure out how in the world their ATVs had gotten so far from the Mason's home. You see, according to the coverage, where the ATVs were found was about four to five miles southeast of the Mason's property, which was not in the direction of the Blue Hole.

Blue Hole was further north of the residents. When detectives informed Martha and Paula about where the ATVs had been found, the women were confused. It just didn't make sense to them that the vehicles had been located so far from where the men had said they planned to go Saturday night. A lead that authorities received rather quickly after that came from two local residents who told detectives they'd heard a volley of gunshots ring out on Saturday night in a wooded area on Signal Mountain known as the Helican. According to a map unsolved mysteries created and an article by the Daily News Journal, that area is slightly northeast of the Mason's property and about five miles from the illegal trash dump where the ATVs were discovered.

Before pursuing that lead further, though, authorities had the ATVs towed from the ravine so they could be examined more closely for potential evidence. Throughout Sunday afternoon and evening, hundreds of people fanned out to search for the missing men, and a few folks even dove down into the blue hole, but no additional clues surfaced from those efforts. The next morning, Monday, July 11th, searching continued, and Detective Sneed and Parham ventured out to the rugged part of the mountain where witnesses had reported hearing those gunshots on Saturday night.

At that location, they saw an old trail that ran through the woods, a few no trespassing signs, and remnants of two wooden fence posts that were rotted but still standing. Like I mentioned earlier, locals referred to this spot as the Helican or the Helican Gate. When Sneed and Parham looked around, they discovered ATV tracks, flies, and over the course of that day and the following day, also uncovered a small cooler and several pools of blood on the ground that looked like someone had attempted to conceal them with vegetation. They also saw suspected drag marks on the forest floor and found at least five spent shotgun shells, as well as three trees near the gate that had been freshly damaged by metal pellets.

Putting two and two together, investigators suspected the fresh markings on the trees and the spent shells suggested someone had recently fired a shotgun in the area. And really it was the discovery of this evidence that told detectives all they needed to know. The Helican gate was most definitely a crime scene. They just didn't know who had been harmed there, but their suspicions were growing

because further investigation of the site turned up hair, bone fragments with traces of lead on them, and pieces of human brain tissue, which only fueled investigators fears that someone, most likely Richard, Kenneth, and Earl, had been severely injured while riding their ATVs there, or they were no longer alive. Hamilton County Sheriff's Department's chief deputy at the time told the Associated Press, quote, I can't confirm it's three people, but I'd be willing to stake money that one's dead. And I'm reasonably sure we'll find three bodies if we find one.

He later continued. The evidence so far indicates at least one suffered a head wound, another probably had upper body injuries. We believe the bikes were hauled out after this and dumped. We believe the bodies were hauled out and dumped. End quote. When news of what authorities had found at the Helican Gate made its way to Martha and Paula, they were, I imagine, shocked and according to some of the source material, reacted in disbelief. The whole time searches for the missing men had been going on,

the women had stayed at home, eagerly waiting by the phone to get an update from officials. And I have to imagine they were hoping the news would be positive, but sadly, it wasn't. Now, to handle the size of the investigation and sheer number of people volunteering to help look for Richard Kenneth and Earl, the sheriff's office set up a command post at an old school in Signal Mountain. From there, they fielded tips and dispatched search crews. According to the television program, Bloodlands, because both Kenneth and Earl were airmen, the Air Force even sent about 100 officers to Tennessee to help scour the mountain. There was also a state marijuana a task force in the area patrolling for illegal crops that assisted in the search.

But unfortunately, even with all those extra resources, the trio remained missing. Then, on Wednesday, July 13th, just two days after the crime scene was discovered at the Helican Gate, investigators caught a break in the case, but not one they necessarily wanted to catch. Around 8 p.m. on Wednesday, July 13th, officials in Marion County, which neighbors Signal Mountain to the west, contacted the Hamilton County Sheriff's Department with some grim news. An elderly couple who lived on a rural road about 10 to 12 miles west of the Helican Gate had discovered three men's bodies piled in an illegal trash dump about 200 feet off the road. These witnesses had noticed a really bad smell lingering in the air, and upon further investigation, realized where it was coming from. When detectives arrived at the site, they saw that two of the deceased men were wearing

flight suits, and I imagine that was pretty much all they needed to see to know that the victims were Kenneth, Earl, and Richard. When the men were found, they'd been stacked on top of one another, with two on the bottom and one on the top lying across the other two. The chief deputy of the sheriff's department at the time told the Associated Press that there were even some indications that all of the victims may have been bound together at some point. It was apparent from their injuries that they'd each been shot

but in different areas on their bodies. For example, Richard had suffered a shotgun blast to his chest while Kenneth had been shot in the left side of his head. Earl had one blast to his right shoulder, which wasn't fatal, and another to his chest that appeared to have been fired into his chest. his heart while he was laying down. Authorities surmised that after seeing Kenneth and Richard get shot, Earl had likely dismounted his ATV and started running, but the killer or killers had cut up to him.

Perhaps most curious of all, though, was the fact that each of the men's shoes had been removed when they were disposed of. The source material doesn't mention that any of the shoes were found near or next to the bodies, so that was definitely a strange detail, and not one that I saw addressed beyond just being initially mentioned. It's weird, even later reporting on this story just doesn't talk about what happened to these men's shoes. But even as puzzling and bizarre as all the case evidence was, though, investigators were

sure of one thing. They had three different crime scenes on their hands. There was the Helican Gate, which was where they believed the three men had been killed. Then there was the big trash dump on Roberts Mill Road where the ATVs had been found. And then finally, there was the body disposal site, way to be able to. further west of those two locations. One prominent theory officials on the case believed was that the bodies were always intended to be found.

Detectives suspected the same thing about the location where the ATVs were ditched. The growing suspicion was that the killer or killers had scattered the ATVs and bodies so far from each other in an attempt to lead law enforcement away from the initial crime scene, the Helican Gate. But things hadn't exactly worked out that way. A member of the sheriff's department told the Associated Press in Kingsport Times news that most likely whoever had committed the crime had moved the victims on all-terrain vehicles through the mountain's back trails.

He said it was unlikely the killer or killers would have loaded the men into a truck or car and risked being spotted while driving on an area roadway. So, to me at least, if that was the case, that suggests whoever did this, had to have some knowledge of Signal Mountain and the connecting trails that led from Hamilton County into Marion County, which is where the men were eventually discovered. It seems unlikely that it was someone who wasn't from the area. By July 15th, the Hamilton County Medical Examiner had conducted the autopsies on the men, and his conclusions about their injuries and manner of death were what everyone sort of expected.

They'd been shot to death, and most likely died on the evening they disappeared. Theories as to why they'd been murdered were all over the place. One investigator told the Associated Press that detectives weren't ruling anything out and they were looking into about 15 different theories. Some of those avenues of investigation included sightings of devil worshippers, mysterious heavy equipment being seen on the mountain around the time of the crime, and so on. According to coverage by Bloodlands, Unsolved Mysteries, and the Tennessean, several tips came in about sightings of vehicles and people on Roberts Mill Road on the evening of July 9th.

But these sightings were all slightly different. For example, one tipster told detectives that he'd seen two men in a blue or silver, possibly Chevrolet truck with three ATVs in the back near the bluff where the vehicles were eventually dumped. Around the same time, about a quarter mile down the road, another motorist claimed they'd seen a woman trying to stop traffic on the roadway and using a red-colored Chevrolet to literally block the road. And there was yet another account by someone else who reported something similar, but claimed the woman he saw had parked a blue-colored Chevy Nova in the roadway to halt traffic.

So yeah, these tips were kind of all over the place, and because there were some discrepancies in the details, authorities didn't know what was legit and where exactly to focus their attention and resources. Another avenue of investigation detectives explored was whether Richard Earl and Kenneth had accidentally stumbled on an illegal cannabis grow in the woods and maybe seen something they shouldn't have. But that theory fizzled out pretty quickly when a search of the woods near the key locations in the crime didn't reveal many crops or major drug operations going on. The sheriff's department also looked into whether someone in Kenneth or Earl's lives had been involved in the crime.

They considered whether the killer or killers had followed the men up from Florida, but after speaking with Paula and some members of the men's squadron at their Air Force base, investigators learned that was unlikely. Both men were well-respected and praised for their good reputations. So detectives then focused their attention on at least two men who lived on Signal Mountain who were known for confronting trespassers on properties adjacent to the Blue Hole and the Helican Gate. These two guys' names were Cecil Hickman and Frank Castile. Cecil worked as a caretaker on a large tract of land for a man who owned a lot of property on the mountain. He got very agitated whenever trespassers showed up. up in the woods. According to one of Richard Mason's good friends, Cecil had had a confrontation

with Richard about eight months before the murders. During that run-in, Cecil had shot into the air near Richard and his friend to run them out of an area he didn't think they had the right to hunt in. According to the book's statement of facts, Cecil had been displaying aggressive behavior like this for several years. So investigators looking into the triple homicide felt like he needed to be looked at very closely as a potential person of interest in the crime. When they dropped by to speak with Cecil, they immediately noticed that he owned a 12-gauge shotgun, which was the type of weapon they believed had been used in the murders. When they questioned him about his prior confrontation with Richard, Cecil admitted that

he'd fired his shotgun near Richard and his companion a while back, but there was no outstanding bad blood between them. When authorities pressed him, he vehemently denied any involvement in the murders and even offered up an alibi for his whereabouts on the afternoon and evening of July He claimed he'd been at a tractor-pool event in Louisville, Kentucky, that Saturday, and a friend of his who was a preacher in Louisville could vouch for him. When investigators followed up to confirm his story, the preacher verified that Cecil had been with him at the tractor pool, and both men had even kept their ticket stubs for

the event, which detectives later confirmed with Cecil was true. So as quickly as Cecil seemed to emerge as a possible suspect, he was ruled out. The other guy authorities were taking a close look at was a local landowner named Frank Castile. Frank was a local mechanical engineer who'd recently purchased about 130 acres of land on Signal Mountain where he planned to build a home with his wife and three children. According to the book's statement of facts, written by Frank's son Franklin Trevor Castile, who most frequently I saw goes by Trevor.

Detectives had first spoken with Frank on the evening of Monday, July 11th at the sheriff's department's command posts, and then later that same night in a detective's car. Frank had received a call from police earlier in the day asking him to come down to the schoolhouse and answer a few questions. According to the book, his son wrote, Frank voluntarily agreed to come by. When his interview got underway, investigators asked him about his property, what he'd been up to on July 9th and 10th, and the types of firearms he owned. All of Frank's answers were pretty straightforward.

He explained that on Saturday evening he'd been celebrating his 22nd wedding anniversary with his wife Susie, and they'd camped together at a clearing on their property near the blue hole. The couple claimed they hadn't heard or seen anything unusual while they were out in the woods. Overnight, their family dog that they'd brought with them had become ill, so around 6.35 the next morning, Sunday the 10th, he and Susie had packed up his jeep scrambler and left the woods, heading in the direction of their house so their dog could take some medicine a vet had previously prescribed for it. On their way, he was way home, though, Frank said that Susie realized she'd left her purse at the campsite, so he'd

volunteered to let her take the Jeep on up to the house, and he'd walk back to their campsite to get her back. A little while later, Susie returned to their campsite, and she and Frank spent Sunday morning and afternoon with some of their mutual friends named Ronnie and Brenda Lewis. As far as firearms he owned, he told the detectives that he had a 22 rifle, a 22 pistol, and a 12-gauge shotgun. And it was his shotgun that he'd actually had to be. And it was his shotgun that he'd actually had with him on the afternoon of July 9th. You see, he said earlier in the day, before he and his wife started celebrating their anniversary, Frank said he'd interacted with two young men who'd driven up along his property toward the Helican Gate. He'd spotted the guys from

a far off, and when they got close enough, he firmly informed them that they weren't welcome and could be charged with trespassing if they came back. Before the two strangers left, Frank asked the men to write their names and information down in a logbook he kept as a way to document the frequency of people who were coming and going from the area. Those guys complied with that request and then left. Frank said he then went back to his normal routine of cleaning up the woods and getting things prepared for his camping trip with his wife. When detectives asked Frank if they could take a look at his logbook, he told them they

were welcome to, and according to what his son wrote in statement of facts, he also allowed them to look over his Jeep scrambler. Authorities eventually took possession of his shotgun, too. Most of the early news coverage of this case doesn't mention Frank Castile by name, but authorities did tell the press that prior to the bodies being found, they had questioned a man who owned the property adjacent to the Helican Gate, where Richard, Kenneth, and Earl were believed to have written their ATVs. It seems from the source material that investigators learned Frank's name

fairly early on in their investigation by checking property and land records, and hearing from people who'd had prior interactions with him for a violent, the no trespassing signs. During some of these encounters, Frank reportedly was always armed. But despite how interested detectives were in Frank as a potential suspect, they didn't have any concrete evidence or eyewitness accounts that tied him to the crime. According to investigative reports by the Nashville, Tennessee Bureau of Investigation Crime Lab cited in the book Statement of Facts, in early August when the fired shotgun shells that had been found at the helicon gate and lead pellets and wadding that were all there too, were tested against Frank's shotgun.

The results indicated that two of the shells were too destroyed to get conclusive info from, but three had been fired from the same gun. However, it didn't appear that those three had been discharged from Frank's firearm, at least not that investigators could say with any certainty. But it's important to note here that just because these five shells were found at the initial crime scene, that doesn't mean they were necessarily associated with the murders. They could have predated the crime. Here's what I mean.

There's always the chance that those shells could have been fired from another shotgun at some point in time before July 9th, since the woods around the helican were used by hunters and locals. I mean, don't get me wrong, it makes total sense to me that investigators looking into the murders would assume these shells were likely connected to the slangs, but it doesn't mean they actually were. It's conceivable that whoever shot Richard, Kenneth, and Earl could have collected spent ammunition after the crime, which to me kind of fits their pattern of behavior, since we know the killer or killers also took so many other steps to cover up the

killings, i.e. spreading the evidence, bodies, ATVs across three different locations. It's also important to understand that ballistics testing on firearm evidence from shotguns is much more challenging than other types of guns. And that's because shotgun rounds discharge pellets that sort of spray out in a much wider pattern, versus a handgun or rifle which shoots bullets that have lands and grooves on them that are easier to analyze for unique identifying characteristics. As part of authorities due diligence, though, they asked Ronnie and Brenda Lewis, that couple who'd hung out with Frank and his wife on the morning and afternoon of Sunday, July 10th, to do an interview. And the Lewis has told Investors,

that nothing had seemed off with Frank when they saw him that day. They described his behavior as normal, not acting nervously or unusual in any way. They said he just seemed like a guy who'd camped out overnight. According to investigative reports cited in statement of facts, later in August, so more than a month after the crime, investigators made copies of Frank and his wife's fingerprints and searched his Jeep, but test results later revealed no traces of bloodstanding were on the vehicle. However, because words spread fast on Signal Mountain and residents were desperate to see someone held accountable for the crime, Frank, and the fact that he'd been questioned, his shotgun

seized, and his Jeep was searched, his family became a bit ostracized, and he was labeled by the public as the prime suspect, even though he wasn't under arrest for the crime. His son wrote in his book that several residents even went as far as signing a petition and sending it to Frank's house to make him aware that he and his first, he and his friend, family were no longer welcome on the mountain. Meanwhile, the Sheriff's Department's investigation was at a standstill. Detectives told the Associated Press and WDEF that they felt like they had a lot of the pieces to the puzzle and might even know who committed the crime, but they needed more evidence to prove it. Tennessee's governor at the time offered up a $5,000 award for information

and crime stoppers even pitched in another $1,000 to encourage witnesses to come forward. But Even when the reward grew to more than $20,000 thanks to other donations, weeks turned to months, and the case remained unsolved with no arrests. Then, in 1989, Unsolved Mysteries began producing a segment about the murders, and when that episode aired in January 1990, the Hamilton County Sheriff's Department was inundated with more than 100 calls about the case. One of which came from a woman who claimed she'd been the person on Roberts Mill Road the night of the crime blocking traffic with a blue Chevy Nova.

According to the coverage about this case, the woman who'd been in the blue Chevy told investigators that the reason she'd blocked traffic on Roberts Mill Road was because her and her husband had been riding around in a dune buggy in the woods and it had broken down. So while she and her husband, or maybe just her husband, worked to put a chain around it to tow it out, she'd position their Chevy with the headlights pointed down into the woods,

and that had required her to stop traffic on the roadway so no one would hit their car. She said she'd never come forward with this information, even when investigators had announced early on that they wanted to speak with whoever owned the Chevy, because at the time her husband had recently been released from prison, and she was afraid that if she came forward and told authorities they'd been riding around in the woods on July 9th,

investigators would try to pin the murders on her husband because of his past criminal history. In the end, that couple was cleared of any involvement in the Signal Mountain murders, and it was just unfortunate timing that authorities didn't know to disregard the sighting of them and their truck sooner. In 1991, three years after the crime,

the case was cold and only growing colder. So the sheriff's office decided to hire an independent investigator to look into the murders, But it doesn't seem like that person made much progress since no arrests happened in 1991, 1992, 1993, or in subsequent years. But then, in the fall of 1996, more than eight years after the killings, something wild happened. Detective Larry Sneed received a phone call from an anonymous woman

who told him that he needed to locate and speak with a woman named Marie Hill if he wanted to solve the case. And Larry wasted no time in tracking down a woman named Marie Hill who lived in Chattanooga. When he knocked on her front door, Marie answered, and one of the first things she said to the detective was that she'd been expecting him to come by, which I have to imagine was a statement

that probably made Detective Sneed's jaw drop. While speaking with Marie, Sneed learned that she'd been in a relationship with Frank Castile for several months, unbeknownst to Frank's wife. According to coverage by the TV program's Bloodlands and City Confidential, Marie indicated to Detective Sneed that she thought Frank might have been involved in the Signal Mountain murders from nearly a decade earlier because she'd gotten several anonymous letters in the mail that outright stated he'd killed the three men.

One of her neighbors had also received a letter that suggested in no uncertain terms that Marie was dating a killer. The accusations were concerning enough to Marie that she'd shown the letters to Frank, but he'd seemingly dismissed them as untrue. Over the course of several months, authorities investigated this lead and even sent the letters to the crime lab for DNA testing. And when the results came back, the conclusions were kind of a bombshell. Frank's wife, Susie Castile's DNA, was found on the papers, and investigators quickly determined

that she was the person behind all of it. But they didn't confront her right away, though. Instead, they set up an elaborate sting operation and wired Marie's house to capture conversations between her and Frank, to see if maybe he'd slip up and reveal something incriminating. That plan sort of blew up, though, on October 12, 1996, when Frank's wife barged in on Marie and Frank at Marie's house late at night and caught the two of them together. Wiretap tapes from that heated confrontation didn't capture Frank stating anything incriminating about the Signal Mountain murders.

But his wife did make some comments, like, quote, I've stood by you for 30 years. I've stood by you through one of the worst things we could ever go through. I had myself drugged down to the police station and fingerprinted because of what you've done. And she also said, quote, what I went through eight years ago doesn't prove to you that I love you, end quote. Which like were definitely declarations that authorities suspected were related to the unsolved. homicides. And more than six months later, on April 15, 1997, investigators felt like they had

enough circumstantial and physical evidence to make an arrest. So they paid 49-year-old Frank a visit at his job near the city of Red Bank, Tennessee, and took him into custody. He was charged with three counts of first-degree murder for the deaths of Richard Mason, Kenneth Griffith, and Earl Smock. A few days after his arrest, prosecutors announced that the district attorney attorney's office would not be seeking the death penalty against him. They cited a lack of eyewitnesses, uncertainty about some of the physical evidence, and the victim's family's preference for seeing their loved one's killer behind bars for life as the reason for not pursuing capital punishment. At his arraignment, Frank pleaded not guilty to the charges against him and was kept in custody

under a $450,000 bond. His defense attorney tried to get a change of venue, but that request was denied. Ultimately, Frank's trial opened in Hamilton County in May of 1998, with jurors that were pulled from another Tennessee County. This compromise was reached after a judge agreed with the defense that Frank likely wouldn't receive a fair trial if all the jurors were people from Hamilton County who'd been following the nonstop publicity about the case. When opening arguments got underway on May 11th, 1998, the state's case was simple. Prosecutors' argued that Frank was overly protective of his property and used the Helican Gate area, which wasn't even technically on his land, to confront people he didn't want using the blue

hole. Investigators believed Frank had gotten into it with Richard, Kenneth, and Earl while they were riding on the old logging trail toward the swimming hole. Prosecutors told jurors that Frank had murdered the men and then taken every precaution to ensure their ATVs and bodies would be found far away from his property. Witnesses, the state presented to support their version of the crime included a parade of a dozen, though some sources say it was as many as 15 people, who had negative interactions with Frank near the Helligan Gate. Marie Hill, his mistress, also testified, as well as the two young men who Frank had confronted earlier in the day on July 9th near his property.

Those two guys testified about how frightened Frank had made them feel when he approached them armed with a shotgun and requested they give him their names, license plate numbers, personal information for his logbook. The prosecution also played the audio tape of the late-night heated confrontation between Frank, his wife, and Marie. But when Susie testified about that whole thing, she told jurors that the claims she'd made in the anonymous letters to Marie and Marie's neighbor accusing Frank of the murders weren't true.

She said she just sent the messages to scare Marie and make her think Frank was a bad guy, so she'd stop seeing him. According to the coverage, prosecutors and investigators were highly suspicious that Frank's wife, and possibly even one of Frank's other sons, could have played a role in covering up the murders in 1988. But neither of them have ever been charged in relation to this crime. And Frank's wife has always stuck to her story that she and Frank were camping and celebrating their wedding anniversary when the slayings occurred. When Marie Hill took the witness stand, she endured a grueling cross-examination from Frank's

defense team, but she maintained that she'd cooperated with law enforcement and allowed detectives to bug her home because she genuinely wanted to know whether the man she'd been having an affair with was actually a murderer. In his own defense, Frank chose to testify too and vehemently denied any involvement in the murders. But according to his defense lawyer, who later spoke with producers for City Confidential, Frank's demeanor and testimony didn't come off well to jurors. His lawyer said that Frank's rebuttal to all of the witnesses who testified against him about his aggressive presence on the mountain was that they were all lying and he was the only person telling the truth. According to an interview Larry Sneed did with City Confidential, there were

a few witnesses that didn't testify during the trial. But if they had, they would have unequivocally refuted Frank's version of events. One witness, the Castile's neighbor, told investigators during their investigation that she saw Frank driving his Jeep scrambler on the morning of Sunday July 10th, and he was coming up from the campsite near the blue hole. But he didn't have the family's dog in the bed. Instead, she saw an ATV. She wouldn't commit to testifying to this information in court, though, because she said that the day after she saw Frank allegedly hauling the ATV, she had received threatening phone calls from an unknown person, and that freaked her out. So after that, she eventually moved to Florida and wanted nothing more to do with the

case. A former prosecutor told City Confidential two other critical witnesses that challenged Frank's version of events were a man and a woman who'd been having an affair in the woods on the night of July 9th, and claimed to see a Jeep hauling several ATVs out of the woods. But even without hearing from these additional witnesses at trial, jurors took less than two hours to deliberate and found Frank guilty of all three murders. A judge sentenced him to life in prison with the possibility of parole after 51 years. After the verdict was read, Frank's son Trevor, who's the author of the book I've mentioned throughout this episode titled Statement of Facts, State v. Castile, told the press that justice had not been served, and he felt sorry for Kenneth Earle and Richard's families

because he wasn't convinced that his father was the person responsible for the three men's deaths. Kenneth's brother Lee told reporters, though, that he wholeheartedly believe Frank was guilty of murder and seeing him convicted brought some closure to the Griffith family. But not a true sense of peace. He said that he'd spent so much time waiting for someone to be held accountable for killing Kenneth and the other men that now that it was all over, he wasn't sure what he was going to do with his time. He explained what he was feeling to the Associated Press this way, quote, I didn't realize how emotionally, physically, and mentally I would be drained by that trial.

You stay on guard every day. You're hearing all the stories all over. The verdict was kind of like a salve to a wound that will never be healed. We'll always miss Kenneth. We had dreams of retiring together and watching our kids grow old. It was all taken away from us. End quote. Unfortunately, Martha Mason, Richard's widow, and Kenneth's mother-in-law passed away before Frank

found guilty, so she never got the opportunity to see justice carried out. Paula, their daughter, and Kenneth's wife, never moved back to Florida after the crime, and eventually remarried. In 1999, Frank appealed his conviction, citing that the trial court had improperly allowed prejudicial testimony and even circumstantial evidence, like the wiretap tapes, in his evidence. In an unexpected twist, the appellate court agreed with some of his arguments, and his conviction was overturned in 2001. He was granted a new trial that year with a jury that had been pulled in nearby Davidson

County. The second trial got underway in April 2003 and lasted a few weeks, and it went a lot like the first trial. Local residents testified about their prior interactions with Frank in the woods. Marie Hill discussed her role in the police sting, and Frank's wife told jurors that she'd come up with the whole letter-writing ruse to simply force Marie and Frank apart, not to paint him as an actual killer. The only big difference between trial number one and trial number two

was that the defense called their own star witness to the stand who hadn't come forward prior to the first trial. This guy's name was Raymond Hardin, and he worked as a junk collector. He told jurors that on the evening of the crime, he was driving in Signal Mountain and saw two men in a black pickup truck disposing of blood-covered ATVs on a local roadway. He claimed to have witnessed this as he drove by in his own car. When he was questioned about why he'd waited so long to come forward with the information,

he claimed he'd stayed silent because he was scared. He said he recognized the two men ditching the all-terrain vehicles as the sons of Cecil Hickman. Yeah, the same Cecil Hickman who authorities had seemingly ruled out as a suspect. And according to Raymond, Cecil's sons were, quote, ruthless people, end quote. So he wasn't keen on ratting on them back in 1988. In the end, though, jurors in the second trial weren't convinced of this new information. In May 2003, they convicted Frank again for the three murders. He appealed that verdict in 2004, but this time the appeals court upheld his conviction.

His attempts to get a third trial were denied. According to the Tennessee Department of Corrections website and coverage by WTVC, Frank died in prison in May 2019. For Kenneth's brother, Lee, Frank's death was a relief. Speaking to the impact that the case had on him and his family, he told WTVC in part, quote, It was like being in a movie that you couldn't turn off. We don't have to devote any more of our lives to this, end quote.

In April 2020, Frank's son published his book about the case titled Statement of Facts, State v. Castile, which, though it does cite some investigative reports, is mostly his personal perspective of the events surrounding the crime, his father's arrest, and the two trials. He admittedly states multiple times in the book that a lot of the writing is just his own opinion. I've read it and agreed that some of the tone is very opinionated, but, hey, anyone is allowed to write a book.

Whichever side you find yourself convinced of in this case, one thing remains true. Three men were killed on Signal Mountain in the summer of 1988, and for what seems to be no real reason. If it really was a turf dispute gone wrong, that's still so sad to me. Earl and Kenneth were young men with their whole lives ahead of them, and Richard was a loving husband and dad who thought he would be safe in a forest he knew like the back of his hand. If you find yourself in the mountains of eastern Tennessee anytime soon, I hope you'll remember these three men's names. I hope you're reminded of them the next time you hear an ATV's motor crank up. And I hope that this story is a reminder that we never really know what ride will be our last.

Park Predators is an audio chuck production. You can view a list of all the source material for this episode on our website, parkpreditors.com. And you can also follow Park Predators on Instagram at Park Predators. I think Chuck would approve.