A woman, director of advertising films, catches the eye of a mysterious young woman dressed in white during an evening of dancing on the terrace of a bar and is fascinated by her.

Michele, a young mathematics professor, moves into a new flat. Lonely, depressed, and neurotic, he spends his free time spying on his neighbors, particularly a young couple struggling with the routines of married life. When Bianca, a new teacher at the local high school, enters his life, Michele finds himself falling in love. At the same time, a string of murders rocks the neighborhood, casting suspicion on him.