Boris Karloff stars as Dr. Garth, the “Mercy Killer” who is on trial for assisting in the suicide of his patient (kinda like a prototype of Jack Kevorkian I guess). While on death row, the court allows Garth to continue his experiments and he winds up creating a serum that restores his youth. The serum also has a peculiar side effect: it turns him into a wild-eyed murderer. Pretty soon, Garth escapes from prison and goes on a killing spree.
This cheapie sci-fi potboiler from
Boris gets the best line of the flick when he says, “Your old age is a disease and I have the cure for it!”