Boston Blackie is a former prison inmate campaigning to outlaw Warden Benton's infamous "Water Cross" torture. Benton, however, is successful in his attempt to have Blackie arrested and returned to the prison, but his evil schemes are ultimately thwarted by Mary Carter, Blackie's girlfriend, who manages to alert the governor. Considered a lost film.

While burgling a mansion, Blackie is interrupted by little Joey, who has been awakened from his slumbers. Blackie gently orders the kid to return to bed, but Joey refuses to do so unless Blackie helps him say his prayers. Thus is formed a strong friendship between Blackie and his "little pal," inspiring our raffish hero to rescue Joey's mother Rosemary Theby from a scandalous situation.

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.

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

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.

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.