U.S Postal Inspectors are called in when a suburban couple are killed by a mail bomb. Suspicion immediately falls on the couple's estranged and heavily in debt son, who also just happens to be a Navy munitions expert. But investigations reveal that he is on the run from a past event in his life that is associated with the bombings.
The second and final Grand National Pictures film to feature The Shadow, played again by Rod La Rocque. In this version, Lamont Cranston is an amateur detective and host of a radio show with his assistant Phoebe (not Margo) Lane. Cabbie Moe Shrevnitz and Commissioner Weston also appear.
Walt Sherill is attacked and beat down by a group of juvenile delinquents on his way home from work one night. The boys who attacked him are not previously known by the police and are therefore hard to track down. As Sherill starts getting impatient he begins his own investigation. Meanwhile, Detective Sergeant Koleski does his best to track down the culprits.
Phil, a part-time truck driver and singer who wears his pants far too high, meets a feisty platinum blonde who challenges him to a drag race through Griffith Park. When he is caught and loses his license, he meets up with the sketchy Frank Wooster who offers him a job singing in his new nightclub. When Phil discovers that his new job also includes drug running, he must fight to save his friends and himself.
A famed trumpet player is suspected of murdering a blues singer. Using only two minor clues, he narrows the suspects to four people, but only after surviving poison placed on the mouthpiece of his trumpet!
Nico, a drug dealer, murders a telegram messenger-boy "for kicks", egged on by partner-in-crime, TV director Francis. Cliff, the boy's older brother, investigates his death due to the slow progress made by the police.
Ma Barker and her four sons terrorize the 1930s South and Midwest with a string of kidnappings, robberies and murders, and even get to work with such famous criminals as John Dillinger and Baby Face Nelson.
Vogel, an important trafficker, betrayed two of his accomplices, Castro and Smith. The first was shot by police, while the latter was imprisoned. Fifteen years later, Vogel adopted a new identity and moved to Jamaica with his wife, Linda. Smith comes back for revenge but Vogel sends his henchmen to kill him.
When he learns that a gangster has taken over his nightclub and murdered his partner, returning WWII hero Joe Miracle steals the money from the club's safe and hides in a settlement home, while the mob is on his tail.
Stunning trophy wife Rachel Avery is stuck in a cold, loveless marriage with her millionaire husband, Holden. So when Holden goes away on a trip, Rachel hooks up with her close friend Carla, and the two hatch a plan to murder Holden and collect on his vast assets. But the girls don't want to commit the crime themselves, so at a bar they seduce a stranger, Travis Brewer, and convince him to do their bidding.
Two industrialists disappear from an airplane while the plane is in the air. Also missing is $100,000. The Falcon investigates and discovers a plot against the government.
Prof. Millard pretends to be dead and helps Jeff King ferret out Vulcan, the evil traitor at the science academy. Donning his Rocket Man costume King goes from one hair raising rescue to the next in order to keep the newly invented Decimator out of the clutches of Vulcan and his minions.
Postal inspectors investigate a con man who uses the identities of others to falsify credit card purchases. Stealing credit card offers from mail boxes, he obtains cards in others' names, makes many purchases until the card is maxed out, but is always careful to pay minimum balances. According to the story, it is possible for individuals such as this to run many credit cards at a time without being caught.
A young girl is travelling to London to find work. Arriving at the station, she meets a man who has been stabbed by a member of a gang of crooks involved with greyhound racing. She becomes a suspect, but flees the scene in order to deliver a message to the dead man's brother. She is protected from the police by a night club entertainer, who she learns is the man she is seeking.
Strange things happen in a revue theatre. The dancer Maria seems to be hunted by an invisible admirer. When the body of a probable FBI agent is found in a trunk the police asks FBI man Joe Como for help. Como gets interested in the revue theatre and an ominous transport firm soon. When he is receiving mysterious threatening letters he is sure that Dr. Mabuse has risen again. But what is going on at "Enterprise X" so that both the goverment and the mad genius in crime are interested in it?