Walter Matthau was not fond of this film. Don Siegel would later say that Matthau hurt this film's box office by publicly stating that he neither liked the film nor understood it.
Character Maynard Boyle's line, "They're gonna strip you naked and go to work on you with a pair of pliers and a blowtorch," is paraphrased in Pulp Fiction (1994) by character Marsellus Wallace.
The crop duster that Varrick (Walter Matthau) attempts to escape in at the end of the movie was destroyed in Oakdale, California on 31 December 1976 during a crop dusting operation. Upon starting a swath run the 33-year-old pilot of the BOEING A75N1 failed to see and avoid wires which caused the aircraft to crash. The pilot was killed in the crash.
The hood wasn't supposed to go up on the getaway car, but director Don Siegel decided to leave it in the movie because it worked within the context of the bungled bank robbery sequence.
Walter Matthau's character makes love repeatedly to Felicia Farr's character. She was the wife of his longtime comedic partner, Jack Lemmon.
Joe Conforte: The owner of Mustang Ranch as himself. (Joseph Conforte ( 10 December 1925 - 4 March 2019 / 93)