The Long Arm (USA: The Third Key) is a 1956 British film noir police procedural crime film starring Jack Hawkins. The film, which was based on a screenplay by Robert Barr and Janet Green, was directed by Charles Frend and produced by Michael Balcon. It was shot on location in London and Snowdonia in North Wales. Two years later Hawkins played a similar role in John Ford's Gideon's Day, a film based on books by John Creasey.