A former San Francisco police detective juggles wrestling with his personal demons and becoming obsessed with the hauntingly beautiful woman he has been hired to trail, who may be deeply disturbed.

Just before hosting a dinner party, Philip Morgan (Farley Granger) and Brandon Shaw (John Dall) strangle a mutual friend to death with a piece of rope, purely as a Nietzsche-inspired philosophical exercise. Hiding the body in a chest upon which they then arrange a buffet dinner, the pair welcome their guests, including the victim's oblivious fiancée (Joan Chandler) and the college professor (James Stewart) whose lectures inadvertently inspired the killing.

A wheelchair-bound photographer spies on his neighbors from his Greenwich Village courtyard apartment window and, despite the skepticism of his fashion-model girlfriend, becomes convinced one of them has committed murder.