The story takes place in the uninhabited American West. In the town of Appaloosa, Averett (Viggo Mortensen) and his partner Virgil (Ed Harris) rely on force and guns to maintain the short peace in the town. The most powerful person in the town is the farmer Randall (Jeremy Irons). With a lot of resources in hand, Randall and his cronies can be described as "rampant" in the town. Finally, after the tragedy happened one after another, the residents of the town decided not to be patient anymore, and a war was about to begin. At the same time, a mysterious beautiful woman named Allison (Renée Zellweger) came to the town. The appearance of this mysterious beautiful woman undoubtedly made the crisis in the town, which was already on the verge of breaking out, worse. This time, can Averett and Virgil rely on each other's tacit understanding and rich experience to lead the residents through this difficult time?