Directed by Mario Bava, this thriller follows Nora Davis (Letícia Román), a mystery novel-loving American tourist who witnesses a brutal murder while visiting Rome. As she becomes entangled in a series of killings, Nora teams up with Dr. Marcello Bassi (John Saxon) to uncover the truth. The film, also known as "La ragazza che sapeva troppo," blends suspense and intrigue as Nora navigates the dangerous path of mystery and danger.