Sach is given a post-hypnotic suggestion that turns him into a championship prizefighter.
It is prior to the commencement of World War II, and Japan's fiendish Black Dragon Society is hatching an evil plot with the Nazis. They instruct a brilliant scientist, Dr. Melcher, to travel to Japan on a secret mission. There he operates on six Japanese conspirators, transforming them to resemble six American leaders. The actual leaders are murdered and replaced with their likeness.
Dr. Bernard Adrian is a kindly scientist who seeks to cure a young woman's polio. He needs human spinal fluid to complete the formula for his experimental serum. Meanwhile, a vicious circus ape has broken out of its cage, and is terrorizing the townspeople. Can there be a connection?
Detective James Lee Wong must find the "Eye of the Daughter of the Moon," a priceless but cursed sapphire stolen in China and smuggled to America. His search takes him into the heart of Chinatown and to the dreaded "House of Hate" to find the deadly gem before it can kill again.
A scientist is turned into an ape man.
The town's leading citizen becomes a homicidal maniac after his wife deserts him.
Shipping magnate Cyrus Wentworth, downcast over a disaster to his ocean liner 'Wentworth Castle' (carrying, oddly enough, an illicit shipment of Chinese bonds) is shot in his office at the very moment of kicking out his daughter's fiance Dick Fleming. Of course, Captain Street arrests Dick, but reporter Bobbie Logan, the attractive thorn in Street's side, is so convinced he's wrong that she enlists the help of detective James Lee Wong to find the real killer.
A young boy witnesses his father murdered by bandits and grows into adulthood vowing revenge.
A young doctor running a health farm for polio victims is dazzled by a pretty and wealthy society girl, to the detriment of his patients and the woman who really loves him.
A schoolteacher comes to a new town and finds herself caught up in the town's problems and disputes.
A mad doctor (Bela Lugosi) and his helpers (John Carradine, George Zucco) lure girls to his lab for brain work, to help his wife.
A man known to be a mute is suspected of committing a murder, as he was noticed at the scene. However, witnesses saw and heard him talking as he was leaving the scene of the crime. The police must determine if he is the actual killer or if he is being framed.
Four scientists and a newsman crash land on Mars and meet martians who act friendly.
When a troupe of showgirls with their impresario and press agent vacation at a Malibu Beach resort, two of them are garroted. Charlie takes on the case assisted by Number Two Son Jimmy and faithful chauffeur Birmingham Brown.
Teenagers try to clear a friend accused of murder.
Slip and Sach's boss, David J. Thurston, has allegedly committed suicide. Slip finds a book of matches with the name of a local nightclub on his boss' desk and finds out from Gabe that a gambling casino is being run out of it. Slip comes to the conclusion that the club had something to do with his boss' death and sets out to find his murderer. The boys get jobs at the club and Louie poses as a rich cattlemen as they gather the information to convict the murderers.
After three men are convicted of bank robberies, Charlie becomes suspicious. After some investigation Charlie finds the men are innocent and that the fingerprint evidence used to convict them had been forged. Charlie then proceeds to find the true bank robbers.
A treasury agent on the trail of counterfeit money confides to fellow ocean liner passenger, Charlie Chan, that there have been two attempts on his life.
A mother and daughter set out on a weekend river rafting retreat, only to encounter 3 escaped convicts along the way.
Slip and Sach take the rap for a robbery they did not commit in order to uncover the real robbers, whom they suspect are led by a convict who gives orders to his gang outside via a short-wave radio stashed somewhere in the prison.