ObscureHollywood.net’s review published on Letterboxd :
An interesting police procedural stars Jack Hawkins as a Scotland Yard Superintendent. Hawkins is investigating a series of robberies in which each safe is opened with a key. Since all the safes are made by the same manufacturer, the search centers on which employee of the manufacturing company is duplicating the keys. The search becomes even more urgent after the thieves commit murder during one of the robberies.
The complex mystery holds the viewer’s attention throughout. Hawkins was a first rate actor.