Southside 1-1000 is a 1950 semidocumentary-style film noir directed by Boris Ingster featuring Don DeFore, Andrea King, George Tobias and Gerald Mohr as the off-screen narrator. It is about a Secret Service agent (Don DeFore) who goes undercover and moves into a hotel run by a beautiful female manager (Andrea King), so that he can investigate a counterfeiting ring. The agent is up against hardened felons such as the gang member played by George Tobias, an unusual example of casting against type for the typically comic actor. It is one of Ingster's two film noirs, the other being Stranger on the Third Floor (1940), which is considered the first noir film.