Filmed at Greystone Mansion in Beverly Hills, California. In 1965, two years after this film was made, The city of Beverly Hills purchased the residence. It was made into a public park in 1971. Tours are available from 10:00 AM to 5:00 PM. Dates and times can be found online.
Troy Melton plays a police officer. As a stunt man, he also doubled for star Kent Taylor.
Greystone mansion was also used in The Loved One, in which one portion of the grounds appeared as the swimming pool where John Gielgud's character hangs himself, and one of the property's garden walkways "portrayed" Poet's Corner in the massive cemetery called Whispering Glades.
Greystone Manor was also used in the season 2 Columbo episode "Dagger of the Mind" as the home of Sir Roger Haversham (John Williams). The butler's (Wilfred Hyde White) residence is also on the property.
Greystone Mansion is also known as the Doheny Estate.