Could there be foul play involved in the tragic death of ‘Friends’ star Matthew Perry? Federal investigators are currently attempting to trace the origin of the fatal dose of ketamine involved in Matthew Perry’s death. According to TMZ, investigators have already “interviewed some key people in Hollywood who are known to have a history of drug use or abuse” in an effort to identify the source. The once shut case was reopened when officials discovered that the ketamine in Perry’s system at the time of his death was not associated with the ketamine infusion therapy that he was undergoing to ease symptoms of depression and anxiety in the weeks leading up to his passing.