In the early 1900s, Buffalo Bill John C. Reilly visits Italy on a tour of his traveling Wild West Show, spreading the myth of American cowboys to a new audience. During a Rome performance, he is challenged by Ercole Rupè Mirko Artuso, a local squire who runs a butteri club and boasts that his butteri are as skilled as Bill’s cowboys. Rupè bets on the American, hoping to prove his own side superior, but the gifted Santino Alessandro Borghi refuses to throw the contest and emerges victorious.
Rupè is betrothed to a charming young French woman, Rosa Nadia Tereszkiewicz, whom he relentlessly abuses and insults. After the win and the failed bet, Rupè confronts Santino as he notices him approaching Rosa. In a volcanic burst of rage, Rupè insults and brutalizes his girlfriend and threatens Santino, but he is ultimately killed by a gunshot fired by Rosa.
Rosa and Santino flee into hiding, dreaming of a trip to America, a dream Rosa holds dear. Rupè’s elderly and incredibly wealthy father places a bounty on the buttero’s head and enlists Buffalo Bill to locate the fugitives. As they escape, Rosa and Santino grow closer and fall in love, getting swept up in a movement of anarchist rebels who see Santino as a symbol of revolt against the social order of the rich and the lords; the group’s leadership is embodied by Rebel Leader Peter Lanzani.
The rebels are suddenly caught in a clash with soldiers, and during the ensuing gunfire, Santino’s fate is sealed by Giovanni “Zecchino” Gabriele Silli, a criminal within the group who, along with his brother, hopes to claim the substantial bounty on Santino’s head. Rosa is kidnapped and wakes in a cave overlooking the sea, bound inside a goat cage, as Zecchino and his brother dispute who will deliver Santino’s severed head to Rupè. The brothers’ fight ends with their deaths, and Rosa manages to escape, dragging Santino’s head with her.
Overcome by despair, fear, and fragments of memory, Rosa imagines Santino’s head still talking to her. Buffalo Bill, trailing with one of his men and the headless body of Santino strapped to Rosa’s horse, confronts the girl and offers a stark choice: a game of heads or tails to decide her fate—if heads, a gunfight; if tails, she’s free to press on. The outcome remains unresolved, but Rosa continues onward, bearing Santino’s head, the horse, and Bill’s notebook.
Eventually, Rosa reaches Rupè and forces him to hand over the promised reward by presenting Santino’s head. After securing the money, she confesses to being Ercole Rupè’s killer, retrieves Santino’s head, and rides again, galloping across the countryside on her white horse.
