Boris Giuliano returns to his beloved land, Sicily, with the task of occupying the post of police commissioner of the mobile squad. Married to the very young Maria, who has yet to finish her university studies, he certainly does not find a good environment in his homeland: in Palermo, the mafia and good society are one and the same thing. Boris does what is asked of a good policeman, to work against crime with commitment and dedication, and in this courageous task he finds the support of his wife. Everything goes more or less well, until Boris arrests some bosses of the Palermo mafia considered untouchable, who are soon released back into the wild.