Lin McAdam is not alone in his hunt for Dutch Henry Brown. Another man, High Spade Frankie Wilson, is also after Dutch for killing his brother. The two men initially team up to track down Dutch, but their partnership is short-lived when they come across a group of Native Americans. High Spade is killed, and McAdam continues on his mission alone.
Meanwhile, Dutch has sold the rifle to a gunrunner named Joe Lamont and his accomplice Waco Johnny Dean. The rifle changes hands several times throughout the film, each time with deadly consequences. Along the way, McAdam crosses paths with a saloon girl named Lola and her abusive ex-lover.
The climax of the film takes place in Laramie, where McAdam finally catches up to Dutch and the two engage in a dramatic shootout. In the end, McAdam comes out victorious and the rifle is returned to him.
Winchester '73 is considered a classic Western and is notable for being one of the first collaborations between director Anthony Mann and actor James Stewart, who went on to make several more Westerns together. The film also features Shelley Winters in one of her earliest roles.