One night in the Old West, a man named Cat Stevens (Terence Hill) tries to ride out of a rough town but is ambushed by a large cluster of armed men. Though wounded, he manages to lure them away and hides in a wagon belonging to a traveling circus. Outside, under the pale moon, the wagons are searched and Cat, along with a trapeze artist named Thomas (Woody Strode)—a former gunfighter—shoot their pursuers, clearing a dangerous path for the moment.
Cat slips away from the circus company as soon as he can travel. That same night, the men return and comb the wagons during the show, leaving behind only traces of his presence. In retaliation, they shoot down Thomas’ partner Joe (Leslie Bailey) during a performance, a brutal reminder of the costs at stake.
Thomas finds Cat and tends to his wounds, insisting that he needs him as bait for my trap. Cat then leads them to Hutch (Bud Spencer), who lives with another big man and a mute figure named Baby Doll (George Eastman). Hutch greets Cat with evident hostility, but Cat explains that Sharp (Enzo Fiermonte), a prospector, needs help stopping mining boss Fisher (Victor Buono) from taking his claim. Cat adds that he had won the deed to the claim in a rigged poker game to take it out of town, which is why he was attacked. Reluctantly, Hutch agrees to join, bringing along Baby Doll for support.
Together they locate the remnants of the circus, now under the direction of Mimi (Lionel Stander), refit the troupe, and gather the artists necessary for a bold confrontation. In the mining town, a county commissioner arrives to review the claims, but the miners are afraid to speak—except for the McGavin family—until Finch’s outlaw gang, in league with Fisher, assaults them with dynamite. At night, a dwarf from the circus slips a message into the commissioner’s room, hinting at an impending plan.
By morning the circus arrives, and the commissioner convinces Fisher to invite everyone to the show. The performance unfolds as pantomimes that dramatize the miners’ plight and the savage killings that have plagued the town. Miners discover guns under their seats, while Fisher’s men uncover feathers, and a fierce fight erupts. The four outsiders, aided by the circus community—including dwarves and can-can dancers—draw the miners into the conflict, and gradually the Finch gang is driven back.
Fisher shoots Mami in the back during the chaos. Cat steps forward and warns him that the gallows await if he presses his luck with the gun. Fisher drops his weapon, and Mami remarks that this turn of events makes him the real clown.
In the end, Cat and Hutch ride off together, their alliance forged in blood and resolve, while Baby Doll, who has begun to speak, stays behind with a can-can dancer at the circus, choosing a new path within the troupe.
