 All of the detectives in the film are parodies of the work of three  authors: Dashiell Hammett (qv), whose Nick Charles and Sam Spade  were the basis for Dick Charleston and Sam Diamond, respectively;  Agatha Christie (qv), whose Hercule Poirot and Miss Marple  inspired Milo Perrier and Miss Marbles; Earl Derr Biggers (qv)  Charlie Chan was the basis for Inspector Sidney Wang and his son.