Alberto is married to a rich and successful businesswoman from Milan, Elvira Almiraghi (Franca Valeri) who has a no-nonsense attitude and barely tolerates the attempts of her husband to keep his factory afloat with her money.

One day a train on which Elvira was supposed to be traveling (to pay visit to her old mother) suffers a horrible accident falling off a bridge and no survivors are reported.

Frustration and anger throw Alberto in a nervous breakdown from which he emerges with a diabolic plan: to sabotage the elevator in the city attic he shares with Elvira to have her killed and inherit her fortune for good.

The German engineer working in his factory agrees with Nardi's plan and with the help of unlikely accomplices like Marquis Stucchi and his own uncle (who acts as Alberto's chauffeur) the murderous project is set in motion, with an unintended and tragicomical result.

The movie is a splendid example of the commedia all'italiana which Risi directs on an unusually black register where Sordi depicts an outrageously sleazy character (arrogant to his subjects, megalomaniac, a bigoted unrepentant fascist who yet longs for recognition from the businessmen who envies).