Gruber (Richard Devon) persuades fellow con Gilbert (Johnny Desmond) to help him break out of San Quentin, Gilbert is vital to the plan as it involves using a plane to fly out of the prison and Gilbert is a pilot.
The plan succeeds but now the escaped convicts face difficulty in getting their hands on Gruber's hidden stash of loot. Gilbert though is more interested in getting to talk to his estranged wife, soon his sister-in-law (Merry Anders) is dragged into their escape with both the police and the mob after them...
A good film with Noir touches, the actual prison break itself only takes up a small part of the film, most of it is taken up with the convicts on the run. This can drag a bit but the menace and violence of the mobsters keeps you interested.