Jim Brown, a running back in the NFL, announced his retirement from American football while making which film?

Jim Brown, the Cleveland Browns NFL running back, announced his retirement from American football at age 29 while making the film "The Dirty Dozen" (1967). The owner of the Browns, Art Modell, demanded Brown choose between football and a professional acting career. With Brown's considerable accomplishments in the sport, he felt it was time to stop playing football and chose acting. As a player, he was already the NFL's all-time leading rusher, was well ahead statistically of the second-leading rusher, and his team had won the 1964 NFL Championship.

In Spike Lee's 2002 documentary "Jim Brown: All-American", Modell admitted he made a huge mistake in forcing Jim Brown to choose between football and Hollywood. He said that if he had it to do over again, he would never have made such a demand. Modell fined Jim Brown the equivalent of over $100 per day, a fine which Brown said that "today wouldn't even buy the doughnuts for a team".

"The Dirty Dozen" is a war film that was directed by Robert Aldrich and produced by Kenneth Hyman. The screenplay is based on the 1965 bestseller "The Dirty Dozen" by E. M. Nathanson. The film stars Lee Marvin, featuring an ensemble supporting cast including Ernest Borgnine, Charles Bronson, Jim Brown, John Cassavetes, George Kennedy, Robert Ryan, Telly Savalas, Robert Webber and Donald Sutherland.

"The Dirty Dozen" was a box office success and won the Academy Award for Best Sound Editing at the 40th Academy Awards in 1968.