***SPOILERS*** ***SPOILERS*** One of the better Blackies, this film is fast paced, good humored, well acted, good fun and has very nice production values.
'Diamond Ed' Barnaby has just been released from prison, according to the Warden, for a charge he "could have beaten." Some of his old 'friends' are very concerned with this; he's been released early and they aren't ready for it. They're very interested in some diamonds he has.
Joe Herschel, the leader of the gang, wants those diamonds, and he tracks down Ed after Ed has put them in a rented box. Joe tells Ed to give him the rocks, but Ed says that they're going to his daughter and to nowhere else. He tells Joe to leave him alone, or he'll have Boston Blackie on his neck.
But Joe's gang takes Ed to an office where they threaten him with a gun. He tells them where the diamonds are, and they leave him tied up. He manages to get to the telephone, and dial the operator. He tells police Inspector Farraday to go to the building that houses the boxes, to look for two men who are going to open box 13 and take the diamonds. But before he can finish the conversation, someone comes into the office and shoots him to death.
Blackie has a key for the box, and he and his sidekick The Runt get there first--just in time for Farraday to nab him.
Farraday has traced the call to the club owned by Joe, but when he brings Blackie and The Runt to the club, Joe denies that anyone was shot in his office or that anyone used his telephone.
Blackie manages to start a fire and escapes. Can Boston Blackie find out who killed 'Diamond Ed' Barnaby, find the diamonds, and restore them to sweet Betty Barnaby, or will the crooks triumph and Blackie end up in prison on a trumped up charge?