The Conformist (1970)

Marcello Clerici had a troubled past, marred by an attempted molestation and a supposed murder, and his desperate bid to fit into a fascist regime. Now, in 1938 Paris, he is sent on his honeymoon to assassinate his former college professor, Luca Quadri, while his wife Giulia remains unaware in their hotel. But his inexistent resolve is tested as he becomes entangled with Quadri's alluring wife, Anna, who harbors dangerous secrets of her own.