The Long Arm (film)

The Long Arm USA The Third Key is a 1956 British police procedural crime film starring Jack Hawkins. The film, which is based on a screenplay by Robert Barr, was directed by Charles Frend and produced by Michael Balcon. It was shot on location in London and Snowdonia in North Wales.

When police respond to a burglar alarm they find nothing amiss after meeting the nightwatchman who allowed them to search the premises. However the next day the safe, having been opened with a key, is found empty. Supt Tom Halliday Jack Hawkins and his new Detective Sergeant, Ward John Stratton, begin searching for the fraudulent nightwatchman.Halliday deduces that the false nightwatchman has committedsafebreaking jobs across the country, all against the same type of safe, all with keys. Visiting the safe maker, Halliday gets the names of all the staff, but they are all cleared. Shortly after another safe is cracked and a bystander is run over as the burglar gets into a getaway car. The victim manages to pass limited information to the police before dying. The hitandrun vehicle is found in a scrap yard. The car had been stolen from a Mrs Elliot and inside they find a newspaper that leads them to a garage in north Wales and a certain Mr Gilson, a deceased former employee of the safe maker. ........

Source: Wikipedia