Have Illinois’ Infamous 1982 Chicago Tylenol Murders Been Solved?

There may be some new developments in a cold case.

If you're not versed in true crime, let's learn some history: in 1982, in Arlington Heights, Elk Grove Village, Schaumburg, Chicago, and Winfield, Tylenol pills were laced with potassium cyanide, killing at least 7 people. It became known as the Tylenol Murders (why do you think Tylenol has the red tamper-resistant lid now?). There has never been a suspect(s) arrested in connection to the crime.

As the case has gone cold over the years, there may finally be some movement with solving it.

In a separate Boise, Idaho cold case, a man known as the "Unknown Wanderer" was found dead in a church in Boise in 1982. Recently, the man was identified as Dr. Mathew Francis Betkouski, who was an organic chemist that had worked for NASA in New Mexico.

Here's where the possible connection (a connection considered likely by high profile forensic psychiatrists and criminal profilers) is to the Tylenol Murders: Dr. Betkouski may be the prime suspect.

In March 1982, Dr. Betkouski commented to another scientist that poison could be introduced into over-the-counter medication and he was particularly interested in cyanide. There was an unsolved cyanide-poisoning case in Las Cruces, around May 1982, after Dr. Betkouski had gone to a pharmacy there looking for pills that he said were for an experiment. He was also found to be taking unauthorized material from the lab he worked in.

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Other findings that make him look sus in the Tylenol Murders: writings from 1980-1981 found that Dr. Betkouski was interested in visiting Chicago and found a Chicago map and a small bottle of cyanide (though it was not the same type of cyanide used in the Chicago murders). After the murders, when he moved to Boise, dye was detected in his hair when he was dead, suggesting that he took steps to conceal his identity.

Ada County Cold Case Detective Tim Cooper sent all this info about Dr. Betkouski to Chicagoland authorities to investigate.

The best-known person associated with the Tylenol Murders was James W. Lewis, who tried to extort Johnson & Johnson for $1 million. He was never convicted.

Netflix renewed interest in the Tylenol Murders case in 2025, when they released a documentary on it.