Sleuth (1972 film) as a full partner. The likeness of actress Joanne Woodward was used for the painting of Marguerite Wyke. The production team intended to reveal as little about the movie as possible so as to make the conclusion a complete surprise to the audience. For this reason there is a false cast list at the beginning of the film which lists fictional people playing roles that do not exist. They are Alec Cawthorne as Inspector Doppler, John Matthews as Detective Sergeant Tarrant, Eve Channing (named after the characters Eve Harrington and Margo Channing from Mankiewicz's 1950 film "All About Eve") as
Margo Lane provide sufficient "vocal contrast". Margo was based on socialite Brenda Frazier and "You Can't Take It with You" star Margot Stevenson. The relationship between Lamont and Margo was modelled on the Thin Man film series. During World War II, Walter B. Gibson felt he could no longer write stories about spy rings, since they had now become a reality. Instead he focused on whodunits, which suited the Cranston persona of the Shadow. Thus the character of Margo came to the fore, and eventually became a permanent fixture in the stories, finally being promoted to a full agent. Margo appears in