Luisa, a socialite, refuses to fund his projects and resents his affair with French citizen Fabienne Béranger (Christine).

Sure enough, they continue to cross paths, and when they meet at a party, Matteo speaks with Stefano alone on the boat ride home to imply he wants something out of their "friendship".

Stefano refuses, but he does forge Luisa’s signature to get the project going, then takes a German woman, Christina Müller (Cardini), home with him.

When Stefan’s returns, the police are crawling throughout his home, the apartment is trashed, and Luisa is strangled to death in her bed with a sock, in what looks like a robbery gone wrong.

Stefano slowly becomes the prime suspect, due to his affairs and business troubles, and he can’t prove what happened the night she was murdered because he can’t find Christina or a ticket he had from passing through a toll booth.