The Third Key (The Long Arm) – Review

London. A gloved figure slowly moves through Stone & Co Ltd on Long Acre street. They check the time on their watch, and then creep up stairs and into an office. A safe is waiting, ready to be opened. A key is used, so it doesn’t even need cracking. However, its opening means an alarm has been triggered. The Scotland Yard Information Room fields the call about the burglary and alerts officers who rush to the scene.

The cops on scene however only find a nightwatchman who lets them in and shows them nothing is wrong. Odd! The next morning Superintendent Tom Halliday (Hawkins) deals with his horrible child Tony at breakfast and thankfully escapes him to the office. He gets a new Detective Sergeant named Ward (Stratton). The pair go to investigate Stone & Co, as the morning staff noted the burglary when the safe was opened, despite the cops finding nothing but a closed safe.

Something nefarious is in the air. Will Halliday and Ward be able to put together a string of clues over a string of possibly related robberies? Can they figure out why the cops on scene were fooled? What connects everything, and how are the robberies being done? Hopefully these men have brains!

This film’s plot contains a fairly solid story and interesting investigatory procedural. It is mostly dialogue and can move slowly in some scenes, but mostly the story itself maintains steam. The Third Key definitely has dialogue and cadence of its time, but it is primarily intelligent and tied to the ongoing investigation plot. The acting fits the times, but doesn’t ruin the experience by being too jarring, and the cast does a fine job

Overall, this decent plot is presented mostly by the books with a steady directorial style. If dialogue heavy cop films are in your wheelhouse, this mystery is not well known and has a few nice wrinkles. There is a little bit of offbeat family interaction for Tom Halliday and his annoying child Tony, but mostly it doesn’t get in the way. Check the film, just don’t miss your train.

Most of the movies below are from the criminal perspective instead of purely the investigation side, but they are similarly themed. Also, I didn't find a trailer, so the opening scene is below.