Unsolved Mysteries Wiki

(from left) Kenneth, Earl, and Richard

Real Names: Kenneth Darrell Griffith, Earl E. Smock, and Richard Mason
Nicknames: Red (Griffith)
Location: Chattanooga, Tennessee
Date: July 9, 1988


Details: On the evening of July 9, 1988, twenty-two-year-old Airman First Class Kenneth Griffith, his twenty-three-year-old friend, Sgt. Earl Smock, and his forty-nine-year-old father-in-law, Richard Mason, planned to ride their ATVs on the trails around Signal Mountain near Chattanooga, Tennessee. Richard's wife, Martha, recalled that they were eager to head out, as they still had a few hours of daylight left. At 6pm, they left the Mason home on their ATVs. By the next morning, they had not returned. Their families were concerned; they were experienced ATV riders and two had rode in the Tennessee backwoods many times before. Fearing foul play, their friends and families began searching.
A few hours later, a local resident stopped to check a bad tire on Roberts Camp Road, five miles from the Mason home. As he looked into a trash dump at the bottom of a nearby bluff, he noticed three ATVs covered with blood. Investigators arrived at the scene and connected the discovery to the missing men. As they retrieved the ATVs, a Signal Mountain resident approached them and said that he had heard gunshots the night before. He said that he had heard the shots near an area known as "the gate".
The next morning, investigators searched the area where the shots had been fired. They found ATV tire tracks on the ground. Nothing seemed out of the ordinary until they approached "the gate", an area posted with no trespassing signs. One of the investigators noticed that a green fly landed on his hand. These types of insects are normally attracted to decaying flesh. A short distance away, just off the road, they discovered a spot of blood on a fallen branch. Nearby, they found what appeared to be drag marks on the ground. Then, they found a pool of blood which had been covered by some leaves. A pocketknife belonging to Kenneth was also found on the ground nearby.
Investigators were certain that the area near "the gate" was the crime scene. Brain tissue and bone fragments were found at the scene. They were certain that the men had been killed. However, no bodies were found there. Two days later, at a dump site eleven miles from the crime scene, their bodies were discovered. Each had been killed by shotgun blasts.

Signal mountain map.jpg

Investigators tried to make sense of the evidence, which was scattered over a large area. The murder site was three miles north of the Mason home. The ATVs were discovered several miles southeast, by Roberts Mill Road. The bodies were dumped by Suck Creek Road, eleven miles from the crime scene.
Based on the physical evidence, investigators have reconstructed the crime. It is believed that the men were riding on the dirt roads when they were confronted by the killer at "the gate". Kenneth was believed to have been shot first; he was shot in the left side of the head. Richard was killed next; he was shot once in the chest. Earl was killed last; he was shot in the right shoulder and attempted to get away. However, the killer caught up with him and shot him through the heart. After the murders, it is believed that the killer carefully covered up the crime scene and then disposed of the other evidence, possibly with the help of an accomplice. They believe that the killer disposed of the ATVs, returned to the crime scene, retrieved the bodies, and dumped them as well.
Investigators believe that the killer wanted the bodies to be found first, in order to prevent the actual crime scene from ever being discovered. It is believed that if the bodies were found on Monday instead of on Wednesday, the crime scene at "the gate" would have never been found.
Investigators are convinced that the killer is a local resident. The residents of Signal Mountain fear that the killer is part of their small community. As a result, they are reluctant to come forward with information about this case.
Suspects: An eyewitness told police that he saw two men in a pickup truck on Roberts Mill Road, the same night the men disappeared. In the back, he saw three ATVs. At the same time that the pickup was spotted, another eyewitness saw a woman frantically trying to stop traffic near Roberts Mill Road. She told the witness that an accident was blocking the road. She was driving a light-colored Chevrolet. This sighting occurred a quarter of a mile from the bluff where the ATVs were discovered.
Investigators believe that the killer is a local resident. He and his accomplice(s) appear to have detailed knowledge of the back roads in Signal Mountain. They also knew the ideal locations to dump the ATVs and the bodies.
Extra Notes: This case first aired on the January 3, 1990 episode. It was also documented on City Confidential and Bloodlands.

Frank Casteel

Results: Solved. On April 15, 1997, fifty-year-old Frank Casteel was arrested and charged with three counts of first-degree murder. He had been considered a suspect from the beginning of the investigation, as he had owned the land where the murders had taken place. It is believed that the men went to a swimming hole known as the "blue hole" on the edge of his property when he confronted them and killed them.
Investigators were aided in their case by new fiber evidence and several additional witnesses. Some of the witnesses came forward as a result of the broadcast. One tipster was the female driver of the Chevrolet. She was not involved in the murders; however, she stated that she tried to direct traffic because her boyfriend's car had broken down. She said that she did not initially come forward because he had spent time in prison and she did not want him to be falsely connected to the murders.
Another tipster led them to Marie Hill, who was having an affair with Casteel. She had received "anonymous" letters from his wife, stating that he was responsible for the murders. He later took one from her and burned it, claiming that it had "harmful" information about him. She later agreed to have her house bugged in an attempt to get a confession from Casteel. However, during their meeting, his wife burst into Marie's home and confronted them both. She noted that she had helped Casteel with "something" on the mountain. However, they did not directly confess to the murders.
Casteel claimed that he and his wife were at a campsite on his property on the night of the murders. It was in close proximity to "the gate". Several witnesses reported hearing gunshots from his property that night. Witnesses also saw him driving his Jeep Scrambler that night. A jeep matching this description was seen later that night with ATVs in the back. Throughout the night, the jeep was seen multiple times near the sites where the ATVs and the bodies were later found.
Early the next morning, a witness saw a woman washing blood out of the back of a jeep at a local car wash. She told him that the blood was from a pig that she had taken to a slaughterhouse. However, the witness was suspicious because slaughterhouses were normally closed on Sundays. He wrote down the license plate of the jeep; it belonged to Casteel. Later that day, a witness (coincidentally Kenneth's brother) was given a ride by Casteel in his jeep. He noticed that the back of the jeep was wet, which was odd since it had not rained recently.
When investigators searched Casteel's campsite a few days after the murders, a burnt blue tarp was found in the fire pit. A witness later testified that he had seen him with a tarp in the back of his jeep on the day of the murders. It is believed that the tarp was used to help cover and transport the bodies. A shotgun was seized from him soon afterwards. It was the same type of weapon that was used to kill the men. However, investigators were not able to directly match it to the bullets used in the murders.
Many of the witnesses that came forward testified that they had been threatened by Casteel after he found them on his property, near "the gate" and the "blue hole". It was also discovered that he had kept a logbook of his encounters with trespassers, usually making them sign the book before letting them go. In the book, he also wrote down most of the trespassers' names, telephone numbers and license plate numbers.
A total of eighteen witnesses testified at Casteel's trial, describing their encounters with him while on his property. In most cases, he threatened them while wielding a shotgun. In some cases, he pointed the shotgun at the heads of the witnesses. Two witnesses testified that on the day of the murders, they were headed to the "blue hole" when he confronted them with a shotgun.
A few weeks before the murders, Casteel told three men to "get off my property or I'll shoot you". A witness also testified that she asked him about dealing with trespassers, and he stated that he "would kill if he had to". Another witness testified that he had fired above the head of his friend while they were trespassing and said that if the trespassing didn't stop, he "would have to start shooting people". Yet another witness testified that one of the trespassers Casteel was annoyed by was "Mason", the last name of one of the victims. He told another witness that he was specifically annoyed by ATV riders and "may have to shoot one of them if [I] have to".
In May 1998, Casteel was convicted of the murders and sentenced to life in prison. He was later given a new trial after it was determined that some of the evidence should not have been admitted; however, he was once again convicted at the second trial in 2003. He died in prison on May 25, 2019 at age seventy-one.