In 1890s Wyoming, Butch Cassidy and The Sundance Kid lead a band of outlaws. When a train robbery goes wrong, they find themselves on the run with a posse hard on their heels. After considering their options, they escape to South America. Wyoming, c. 1900s. Butch Cassidy (Paul Newman) and the Sundance Kid (Robert Redford), the leaders of the famous Hole in the Wall Gang, are planning another bank robbery. As they return to their hideout in Hole-in-the-Wall, they find out that the gang has selected a new leader, Harvey Logan. He challenges Butch to a knife fight, which Butch wins, using a ruse. Logan had the idea to rob the Union Pacific Flyer train instead of banks. He wanted to rob it twice, the idea being that the return would be considered safe and therefore more money might be involved. Butch takes this idea as his own. The first robbery goes very well and the Marshal of the next town can't manage to raise a posse. Butch and Sundance listen to his attempts, enjoying themselves. Sundance's lover, Etta Place (Katherine Ross), is introduced. But obviously both men vie for her attention as she also goes bike-riding with Butch, a dialogue-free part of the film, accompanied by 'Raindrops Keep Falling on My Head'. The second robbery goes wrong. Not only does Butch use too much dynamite to blow the safe, but also a second train arrives, which is carrying a posse of six heavily armed men on horseback that has been specially outfitted to hunt down Butch and Sundance. The gang flees, but the entire posse follows Butch and Sundance...

This movie is a comedic retelling of the early days of Butch Cassidy and the Sundance Kid. It follows their hilarious and adventurous journey as they become outlaws, rob banks, and escape from prison.