After being imprisoned in Alcatraz for petty theft, Henri Young leads a failed escape attempt from the infamous prison. As punishment for the doomed getaway, prison warden Milton Glenn places Young in solitary confinement for three years. When Young is finally released from his torturous ordeal, now a completely broken man, he kills an inmate and is charged with murder in the first degree. Although it initially appears to be an open-and-shut case, after Young's attorney James Stamphill learns the facts of Young's time in solitary confinement, he launches a daring defense that blames Alcatraz's inhumane conditions for driving Young to insanity and therefore causing him to kill.