Driscoll began experimenting with drugs at age 17, becoming hooked on heroin, and was arrested for the first time in 1956 for possession of marijuana, but the charge was dismissed. Late in 1961, he was sentenced as a drug addict and imprisoned at the Narcotic Rehabilitation Center of the California Institution for Men in Chino, Calif. He was released in 1962, but couldn't find any roles and eventually ended up in New York City working with Andy Warhol's art collective The Factory. He disappeared in late 1967 or early 1968, with two boys playing in a deserted Manhattan tenement eventually finding his body on March 30, 1968, about three weeks after his 31st birthday. His cause of death was determined as heart failure caused by advanced hardening of the arteries due to his longtime drug use. With no identification on his body, his remains went unclaimed and he was buried in an unmarked pauper's grave in New York City. His identity was only discovered about 19 months later due to a fingerprint match.