Producer Walter Wanger, who had just been released from a prison term after shooting a man he believed was having an affair with his wife, wanted to make a film about the appalling conditions he saw while he was incarcerated. He got together with director Don Siegel and they came up with this film, in which several prison inmates, to protest brutal guards, substandard food, overcrowding and barely livable conditions, stage an uprising, in which most of the inmates join, and take several guards hostage. Negotiations between the inmates and prison officials are stymied, however, by politicians interfering with the prison administration, and by dissension and infighting in the inmates' own ranks.