Filmed in semi-documentary fashion, House on 92nd Street is a "now it can be told" drama about the smashing of a Nazi spy ring operating the U.S. Thanks to covert surveillance, the FBI learns of the presence of several suspicious persons in NYC. William Eythe is a German-American college student approached by the spies to become a secret Nazi operative. Eythe instead heads directly to FBI chief Lloyd Nolan and offers his services as a double agent. His mission is to locate the head of the spy ring, an unseen figure known only as Mr. Christopher, and to that end Eythe infiltrates the ring, headquarted in a town house on 92nd street. Among the conspirators are an erudite German colonel (Leo G. Carroll) and the beautiful female owner of the house (Signe Hasso). Part of the plot involves the smuggling to Germany of America's atomic secrets by a weak-willed document clerk (played by Gene Lockhart, one of the best "cringers" in the business). Dwelling a bit too long on the meticulous research techniques of the FBI, House on 92nd Street picks up momentum in the final sequence, wherein "Mr. Christopher" is revealed and double agent Eythe barely escapes with his skin intact.