A British engineer tries to convince the Mafia to allow an oil refinery on some prime waterfront real estate in Sicily. Proby (Peter McEnery) talks to the mob bosses about the project, but disagreements in the Mafia soon surface. One faction wants the refinery, the other a beachfront resort. Comedy ensues when Proby falls for the beautiful daughter of a mafioso, leading to a family argument. Rosa (Virna Lisi) is engaged to a mobster and causes a stir when she professes her love for the persistent Proby. The mob fights over which direction to choose for the property, as Proby and Rosa fall in love in this romantic comedy adventure.