In this musical based on the Broadway show, Ben Rumson (Lee Marvin) happens upon a wrecked wagon containing a dead man and his surviving brother, Pardner (Clint Eastwood), in the wilds of California during the Gold Rush. At the burial, they discover gold dust and stake a claim. Soon a mining camp dubbed "No Name City" emerges, rife with lonely men starved for female companionship. When a polygamist Mormon arrives looking to sell off a wife (Jean Seberg), a bidding war commences.