A bored couple turns to voyeurism to enhance their sex lives, but are themselves the object of another voyeur's obsession.

When Massa is released from prison, he's sure that Luciano, an old freind, is responsible for his incarceration. Massa proceeds to keep watch on Luciano, who has been living with Massa's beloved sister Maria. Feeling doubly betrayed because of his unhealthy adoration for Maria, Massa is determined to get back at Luciano and ends up in a deadly game of roulette.