Written by real-life intelligence agent Ladislas Fodor, Cairo is both a spoof of espionage thrillers and a good-natured refutation of Jeanette MacDonald's established screen image (it was her last film on her MGM contract). MacDonald plays wisecracking movie star Marcia Warren, who while "between pictures" in London hires fellow American Homer Smith (Robert Young) as her butler. What Marcia doesn't know is that Smith is an American newspaperman, who strongly suspects that our heroine is a Nazi spy (the real enemy agent is played by Mona Barrie, who looks not at all like dear Marcia). All such misunderstandings are forgotten once the principal characters end up in Cairo, with Marcia and her maidservant Cleona (Ethel Waters) pitching in to help Smith break up an Axis espionage ring. There are "in jokes" aplenty in Cairo, ranging from Jeanette MacDonald's flippant reference to her 1936 film hit San Francisco to the "it's only a movie, folks" closing shot. The music isn't bad, either.