Ride the High Country - Sam Peckinpah

Aging ex-marshal Steve Judd is hired by a bank to transport a gold shipment through dangerous territory. He hires an old partner, Gil Westrum, and his young protege Heck to assist him. Steve doesn't know, however, that Gil and Heck plan to steal the gold, with or without Steve's help. On the trail, the three get involved in a young woman's desire to escape first from her father, then from her fiance and his dangerously psychotic brothers.