Crimen en Montecarlo

Three Italian couples, from the working (Quirino: Nino Manfredi, Girolimoni, and Giovanna: Franca Valeri, Il Vedovo), middle (Remo: Vittorio Gassman, Il Mattatore, and Marina: Silvana Mangano, Riso amaro), and upper (Alberto: Alberto Sordi, I Vitelloni, and Eleonora: Dorian Gray, Mogli pericolose) classes, arriving from Rome in Monte-Carlo, get involved by mistake in the murder of the wealthy old lady Van Zungguer.

Systematically lying by fear and clumsiness to the commissioner (Bernard Blier, Il Gobbo), they get quickly suspected then arrested. Will they be able to prove their innocence by telling at last the truth? Won't they instead go on contradicting each other while trying to escape the law? Shall the real murderers finally be able to get caught? This zany comedy drives its colorful characters to get lost in inextricable situations within a small foreign country.