A new TV series on the Oxygen cable channel will examine the 2008 death of a Wilmington man who a pair of retired New York City detectives believe may have been killed by an apparent group of murderers known as the “Smiley Face Killers.” The episode focusing on Thomas Booth is set to air this weekend.

First theorized by Sgt. Kevin Gannon and Detective Anthony Duarte in 2008, the Smiley Face Killers, which may operate as a network throughout the country, reportedly target college-age white males; they are found drowned weeks after they disappear. Other alleged elements of the slayings include stealing only the victim’s cell phone and leaving graffiti at the scene. Gannon and Duarte claim that the group could be responsible for upward of 40 deaths across 11 states in 10 years, according to a Daily News report, but the theory has been discounted by several police departments, as well as the FBI.

Oxygen’s Smiley Face Killers: The Hunt for Justice on Saturday will investigate the death of Thomas Booth, a 24-year-old Wilmington drywall finisher who was found dead behind Bootlegger’s Bar in Woodlyn, Ridley Township, Delaware County, in February 2008. According to reports, Booth visited the bar with friends the night of Jan. 19, but wasn’t seen again. Authorities found his body two weeks later in a shallow portion of Ridley Creek about 30 yards from Bootlegger’s’ back door.

With no signs of trauma to the body, Booth’s death was ruled an accidental drowning. However, some aspects of his death seemed off to friends, family, and investigators.

Booth was healthy, and though he had epilepsy, his family said at the time that he had not had a seizure for more than two years, according to the Delaware County Daily Times. At the time of his death, examiners found, he had a small amount of Xanax in his system that was consistent with a prescription, and his blood-alcohol content was about 0.20, which authorities told the Times would not be high enough to “make him incoherent.”

Booth’s body was without his cell phone, but had his wallet, money, and ID. His mother, Barbara McKay Bush, meanwhile, said she was confused why Booth was near water at all, as he “never liked the water,” let alone in the middle of January, she told the Daily News in 2008.

And then there was the graffiti investigators found. Painted below Bootlegger’s’ back deck, it consisted of a simple smiley face with a crown — a supposed calling card of the purported Smiley Face Killers.

According to a 2008 Daily News article, then-Ridley Township Police Detective Sgt. Scott Willoughby, who was promoted to captain in 2015, began suspecting the group’s possible involvement after seeing a Good Morning America segment about the Smiley Face Killers around May that year. As he told the Daily News, many elements of Booth’s death lined up with elements of other purported Smiley Face Killers murders, and although he didn’t accept the theory fully, it did get his attention.

“I find the circumstances puzzling even without this theory,” he said. “Some of the clues to their puzzle match some of the clues to this puzzle. That’s why I think we need to investigate all clues and all avenues.”

The FBI, however, has discounted the Smiley Face Killers theory, saying many of the deaths Gannon and Duarte pointed to “appear to be alcohol-related drownings.” Special Agent Richard J. Kolko told the Daily News that the FBI determined “there is no serial killer or killers.”

But with the debut of Oxygen’s Smiley Face Killers: The Hunt for Justice, the topic is back in the news. The series, which premiered last month, has looked at the deaths of Dakota James, Lucas Homan, Will Hurley, and Brian Welzien, all healthy white males in their 20s who officially died in accidental drownings after drinking on nights out between 2006 and 2017.

Featuring Gannon and Duarte and their team of investigators, the show aims to “investigate these deaths as homicides” to “establish a possible connection” in hope of furthering their theory, according to a release. In the episode dealing with Booth’s death, the investigators speak to friends and family about the possibility that Booth was murdered by the group.

Smiley Face Killers: The Hunt for Justice airs Saturdays at 7 p.m. on Oxygen.