Spaghetti at Midnight (movie, 1981)

Savino La Gastra discovers his wife Celeste has a liaison with an architect: Andrea. Even if also Savino has a story with Elvira, a judge's wife, he decides anyway to ask to a mobster to kill his wife. In the mean time Celeste is organizing a surprise party for Savino's birthday, and that day things start to get complicated. First Savino kills accidentally the mafia killer in charge to kill Celeste; second his lover Elvira arrives to the party with the judge... not to mention the police and the mafia Don...