Cat Stevens wins a high stakes poker game. Still on his way out of town, he is attacked and badly wounded by an unscrupulous gang. With the last of his strength, he manages to escape and hide in the wagon of a travelling circus, where he is finally discovered by the circus people. The former revolver hero Thomas and the circus director Mimi decide to help the injured man. When they arrive in the next town, the still very weakened Cat leaves the circus people, because his presence poses a danger to the them. But it's already too late. During the performance, the bandits search the circus caravan and discover the bloody dressing material with which the circus director had covered the wounds of Cat. One of the bandits shoots through the rope of the artist Joe, whereupon he crashes from high altitude and dies. Thomas, who had to watch the crash, swears revenge and takes up the trail of the bandits. He meets Cat again. Together they make their way to Cats old buddy Hutch. Here we learn what the poker game was all about. It was faked between Cat and the gold prospector Sharpe, as the gold prospectors of the area can no longer be sure of their lives, since the unscrupulous businessman Finch and his gang have tried with all means to acquire the various gold claims. Sharpe also fears for his life and with the faked poker game he gives his gold claim to his buddy Cat in an inconspicuous way. Cat convinces Hutch and his helper Baby Doll to help them to fight against the bandits. The four gunmen ride back to the circus, drum the entire circus team together and then move with the circus directly into the lion's den. With an ingenious trick, they manage to surprise and eliminate a large part of the gang in the circus. But the gold prospectors are still too intimidated to take up the fight against the rest of the bandits. In the city there is a big showdown.
Boot Hill is a sequel of Ace High. It marks the end of the trilogy about the Western heroes Cat Stevens and Hutch Bessy. It is also the third film of the duo Bud Spencer and Terence Hill.