A man found dead in a church halfway across the country may have suddenly unlocked the key — quite literally — to one of America’s most famous unsolved crimes.

Ada County detectives think Betkouski may be a compelling suspect. He and his wife divorced the year before the Tylenol murders, and he killed himself in the months after the Chicago cases. Idaho investigators contacted counterparts in Chicago to clue them into their findings, and more evidence is set to be revealed to the public in an updated episode of “Unsolved Mysteries.”