Reportedly, producer Leonard Freeman clashed with director Ted Post during production. One day Freeman showed up on the set, issuing orders and taking charge. Post wanted to confront him, but Clint Eastwood intervened. Eastwood spoke to Freeman, and Freeman left the set and didn't return. What he said was, "If you show up on this set again, there won't be a set ... won't be a cast, won't be a crew."
Inger Stevens had never heard of Clint Eastwood before she was cast in the film. Once they met she began to like him very much and they ended up having a brief affair. When the film was finished, Stevens told director Ted Post, "Anytime you do a picture with Clint and there's a part in it, call me."
First of three cinematic films that actor Pat Hingle made with Clint Eastwood. The pictures are (in order): Hang 'Em High (1968), The Gauntlet (1977) and Sudden Impact (1983). Each picture was made in a different decade, one in the 60s, one in the 70s and one in the 80s. The pair also collaborated on the TV episode Rawhide: The Book (1965). Both Hang 'Em High (1968) and Sudden Impact (1983) feature Eastwood as a tough guy lawman who borderlines on vigilantism and Hingle as his superior who has a heavy disdain for the way he does things.
Mel Goldberg and Leonard Freeman were first told that Clint Walker was cast in the lead but were severely disappointed when they were informed that it was actually Clint "Easterwood." Needless to say it worked out better than if it had been Clint Walker.
The trivia item below may give away important plot points.
Ed Begley and Inger Stevens died within 2 days of each other in April 1970 in Hollywood. Begley died at age 69 of a heart attack and Stevens at age 35 by suicide, the same way Begley's character died in this movie. Stevens was the first of three of Clint Eastwood's leading ladies to commit suicide, the others being Jean Seberg (Paint Your Wagon (1969)) who took an overdose of barbiturates in 1979, and Elizabeth Hartman (The Beguiled (1971)) who jumped out of a fifth-story window in 1987.