Gentleman crook Boston Blackie answers a want ad for an expert safecracker placed by Doris Macon, who claims a moral right to the safe's contents. She hires Blackie, and they break into the house where the safe is kept. Blackie blows up the safe just as owner Captain von Hoffmeier returns home. Doris disappears with papers from inside the safe, while Blackie takes phonograph records, which, when played with a special needle, reveal secrets that implicate von Hoffmeier as a German political spy.

A mad scramble for stolen loot ensues after Boston Blackie has prisoners released for work in a wartime defence plant.

Boston Blackie, in the 11th film of the Columbia series, indulges in some wit-trading with a squirmy spiritualist who deals in blackmail, murder and the occult. "Blackie" out to help his pal, "Runt," recover some jewels, finds himself involved in the homicides, and also finds himself as the prime suspect, and now has to find the real culprit in order to clear himself. So "Blackie,", a man of many talents and already a proved magician from cases past, shows he knows a little bit about dancing skeletons, walking phantoms and spiritualism himself, and holds a séance to unmask the murderer.

After a rare gem is stolen from an exhibition at a posh hotel, Inspector Farraday decides to recruit former thief Boston Blackie to find the stone. Along with his assistant, "The Runt", Blackie focuses his investigation on the hotel manager, George Daley, and his sister, Eileen. Through disguises and ruses, Blackie and the Runt try to trick their way to discovering the thieves.

Blackie is the natural suspect when an expensive pearl necklace is stolen while he is supposed to be guarding it.

Blackie is arrested when retrieving stolen gems from a safety deposit box for a friend.

Blackie helps the police rescue hostage from an escaped maniac on a killing spree.

Blackie performs in a magic show at a women's prison, which gives an inmate an opportunity to escape.

Blackie receives a call from a friend who asks him to retrieve some money from his apartment and deliver it to him in California. Performing this good deed, he is accused of theft, but is allowed to proceed to Hollywood to help the police find a lost diamond.

Blackie is seen leaving a Chinese laundry where the proprietor has been murdered, and must track down the real killer in Chinatown.

A murder is committed during the auction of a valuable statue. The prime suspect is Boston Blackie, whose reputation for living on the edge of the law makes him an easy target for the police. When the body disappears, Blackie must find it to prove his innocence.

Boston Blackie Dawson gets some jewels that belonged to the imperial family of Russia. A gang of terrorists is after the jewels.