Three bank robbers (J. Carroll Naish, Lee Marvin, Stephen McNally) case a small Arizona mining town prior to pulling a holdup. The audience get to know the various townsfolk as they're scrutinized by the crooks. Victor Mature plays a man who is a disappointment to his son because he didn't serve in the war.
Tommy Noonan is a meek bank manager with a habit of spying on a pretty customer as she undresses in her second-story bedroom. Sylvia Sidney is a petty thief who has deposited her stolen funds in the bank. Margaret Hayes is the cheating wife of a local leading citizen, who is killed in the holdup.
And Ernest Borgnine is a pacifistic Amish farmer, forced to take violent action when his children are threatened by the criminals (Borgnine's pitchfork-wielding scene was reproduced for the print ads of this film, leading some critics to assume that he was the villain!) The hero of the day turns out to be the unheroic Mature, who after being kidnapped by the crooks frees himself and prevents their escape.
Violent Saturday is based on a novel by William I. Heath.