The Ada County Sheriff’s Office in Boise, Idaho has finally figured out the real identity of “The Unknown Wanderer,” a man who went by the alias William M. Toomey and died by suicide in a local church in 1982. It’s cool to close any cold case, but this previously unsolved mystery looks like it may crack an even bigger one: Toomey, whose real identity was revealed on Wednesday to be Dr. Mathew Francis Betkouski, an organic chemist, may also be the infamous Tylenol Murderer. Enter: Unsolved Mysteries.
Today’s press conference was a joint effort between Ada County Sheriff’s Office and the long-running true crime brand, which is a bit unusual. Unsolved Mysteries was there not for “The Unknown Wanderer” necessarily, but for his potential ties to the Chicago-area poisonings that left at least seven people dead. In 1982, the Tylenol Murderer uncapped bottles of the popular pain medicine at various stores, dumped the powder contents of capsules out, replaced it with cyanide, and returned the bottles to store shelves. (This was before the advent of the safety seal and directly led to its widespread adoption.)
Betkouski’s cause of death was deemed to be cyanide ingestion. Betkouski went through a lot of effort to change his appearance prior to his suicide, and it is believed by some that he made confession in Sacred Heart Catholic Church, where his body was discovered. The Tylenol Murders were never solved.
“He was a brilliant man, but he struggled to connect with people in life,” Ada County Sheriff’s Office Det. Tim Cooper said of Betkouski on Wednesday. “Dr. Betkouski had a documented fascination with chemistry and the use of explosives from a young age, and did put others at risk on more than one occasion.”
“In 1974, Dr. Betkouski sustained a traumatic brain injury, which caused some of his problems to manifest in more concerning ways than they had before,” Cooper continued. “In 1975, Dr. Betkouski worked for a flavors and fragrances company in the Jacksonville area, and after about three years, concerns mounted after coworkers reported Dr. Betkouski discussing the perfect crime and how cyanide could be used as a less messy means of taking one’s life.”
It gets worse: Betkouski was fired by Lockhead in 1982 “following an incident at a local pharmacy.” Betkouski “attempted to obtain some type of pills or capsules…for an experiment,” Cooper said.
“Where this leaves us is while our office may have identified some possible connection between Dr. Betkowski and the [Tylenol Murders], we’re not naming him as a suspect, and we cannot say he was in Chicago during the final week of September 1982,” Sullivan said. “More information does exist in this case that we won’t be releasing today.”
It is not on Ada County to name Betkouski as a suspect in the Tylenol Murders as that is a Chicago case. The Idaho police did share all of their findings with the Chicago PD.
All of Cooper’s findings and more is comprehensively covered in documentary Unmasking the Tylenol Killer, which premieres on The Roku Channel on October 9, 2026.
“This case and everything you’ve heard today is going to be the subject of a brand-new Unsolved Mysteries documentary called Unmasking the Tylenol Killer. It streams October 9 on the Roku Channel, and it’s going to go into detail we simply don’t have time for today,” Sheriff Matt Clifford said at the press conference. “Our goal in working with Unsolved Mysteries was simple: we wanted more tips, and we wanted more evidence to come forward.”
James Lewis in Netflix’s ‘Cold Case: The Tylenol Murders.’
Courtesy of Netflix
If this all sounds familiar, that’s probably because Netflix tried it. In 2025, Joe Berlinger’s Cold Case: The Tylenol Murders attempted to solve the now-44-year-old killing spree. Directors Yotam Guendelman and Ari Pines (well, really it was producer Molly Forster) got the FBI’s lone suspect James Lewis to participate in the three-part series, but it now appears Lewis is probably not their man.
Lewis was never charged in the poisonings, but he was convicted of extortion for sending a letter to Tylenol maker Johnson & Johnson taking responsibility for the deaths and demanding $1 million to stop them. Lewis said later that his letter was an attempt to point authorities to his wife’s former boss. Lewis got a 10-year prison sentence, and died shortly after the three-part Netflix series wrapped.