Another in a unrelated series of Warner's penitentiary tours in three different decades. This one is California's notorious Folsom Prison prior to its 1944 reformation make-over. Ben Rickey, the prison's sadistic old-school warden who believes that the prison system if for punishment rather than reformation, rules Folsom with an iron-hand. He highly resents his university-trained assistant, Mark Benson, who does not share Rickey's beliefs. Rickey, hoping the results will be disastrous, gives Benson permission to try his modern method. He tolerates Benson's innovations until convict "Red" Pardue is killed by another prisoner. Benson blames Rickey, who had refused Pardue protection after he had reported an escape attempt. Benson resigns and Rickey brings back his concentration-camp program. Chuck Daniels, a hardened convict, then stage his long-planned prison break. A bloody riot ensues in which Rickey is murdered and the escapees are accidentally killed by a dynamite blast while taking revenge on a treacherous convict.