Carroll Baker plays the eponymous Deborah, who has travelled to Geneva from her home in the United States to celebrate marrying her handsome husband Marcel (Jean Sorel). However, the celebrations are short-lived when Marcel spots an old friend, Philip (Luigi Pistilli), who snubs him at a nightclub. Accosting him outside, Philip testily tells Marcel that he blames him for the death of Suzanne (Evelyn Stewart)​—who supposedly killed herself after he left for the United States.