Charlie Chan in the Secret Service
Charlie Chan in the Secret Service is a 1944 mystery film starring Sidney Toler as Charlie Chan. It is the first film made by Monogram Pictures after the series was dropped by 20th Century Fox, and it marks the introduction of Number Three Son (Benson Fong) and taxi driver (later Chan's chauffeur), Birmingham Brown (Mantan Moreland). Plot. In the two years since the last Charlie Chan feature film ("Castle in the Desert"), Charlie Chan is now an agent of the U.S. government working in Washington DC and he is assigned to investigate the  murder of the inventor of a highly advanced torpedo. Aiding Chan is his overeager but dull-witted Number Three son Tommy (Benson Fong) and his Number Two Daughter Iris Chan (Marianne Quon). Also involved in the case is the bumbling and easily frightened Birmingham Brown (Mantan Moreland) who works as a limo driver for one of the suspects. Production. 20th Century Fox stopped making Charlie Chan films in 1941. In May 1943 Monogram Pictures announced they had purchased the rights to the character from Fox and would make two Charlie Chan films a year. Sidney Toler would reprise his performance  as Chan. Keye Luke was reportedly unable to reprise his role as Number One Son, so a search started for an actor to portray Chan's son. In June 1943 Monogram Pictures announced "Charlie Chan and the Secret Service" would be one of 24 movies and 16 Westerns the studio would make over the following year. This was eight less than the previous year as Monogram said they wanted to make "fewer and higher budgeted pictures". The film was to star Sidney Toler and also include Iris Wong from the Fox movies. In July 1943 Benson Fong was signed to  play Chan's son. Wong eventually was replaced by Marianne Quon. Filming started 10 September 1943.