Bob Hope once called Willie Best "one of the finest actors I've ever worked with."
Bob Hope is said to have enjoyed this role since it was a total change of pace for him. In most of his films he portrays a coward while, in this one, he is heroic.
A joke about Democrats being like zombies has been pointed to for years as evidence of Bob Hope's political affiliations. In fact, Hope made jokes at the expense of both parties throughout his long career, during which he was on good terms with many presidents, Democrat and Republican.
The play, "The Ghost Breaker," by Paul Dickey and Charles W. Goddard, was made twice as a silent film, in 1914 (directed by Cecil B. DeMille), and in 1922. Both silent versions are considered lost. The play was filmed a final time as Scared Stiff (1953), starring Dean Martin and Jerry Lewis. Bob Hope made a cameo appearance in that film.
The castle in the story is called "Castillo Maldito". It means "Castle of the Damned", or "Evil Castle".