Trapped by Boston Blackie

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

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.

It is the Christmas Holidays and reformed thief, Boston Blackie goes to Castle Theater to pick up players who will perform for prisoners that are still in prison. He takes a girl with him who has a brother already in prison. She has visited the prison twice in the month, so is not suppose to visit again. However when the group is completed the girl is included as well as Inspector Farrady. One of the clowns in the show is kidnapped and replaced by a con who wants to get even with two ex-partners. Boston Blackie figures out that a con has replaced one of his clowns but is unable to stop him. Blackie's clothes are stolen and a murder is committed. Of course, the Inspector immediately suspects Blackie of being involved. Now it is Blackie's job to find the killer, exonerate himself and help the girl free her brother.

When a murder occurs on an ocean liner docked in New York, the trail leads to Coney Island and a spy ring.

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 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.