The flashback scenes show the two Italian immigrants (who arrived in the US as children) find work in a Turkish bath frequented by people linked to the underworld, including Attanasia, one of the most powerful bosses in New York, and Jarchin Enriquez known as the Scarred man.

At this point the two cousins are involved in a firefight between the two rival gangs who, through their involuntary complicity, save their lives and that of Attanasia, who invites them to his villa to repay their debt.

Franco and Ciccio are unexpectedly entangled in the affairs of the boss, who manages to immerse himself in the world of boxing and comes into conflict with Lemmy Tristan, his enemy.

Attanasia decides to fix all the matches to facilitate the cousins' journey to fight for the world title, while Tristan's attempt to kill Franco fails.

In the meantime, Franco and Ciccio learn of Attanasia's plans and try to escape, but are stopped by the latter's henchmen and forced to have to dispute the match with Frederick Jones, Tristan's trusted boxer.

Thanks to a series of tragicomic events, the two cousins still manage to make fun of Jones, winning the world title and earning the hatred of Attanasia, who will find himself in a firefight with Tristan, the latter convinced he has been deceived.