When a police officer is murdered, Captain Street looks to Mr. Wong to catch the killer. Prime Suspect: Frank Belden Jr., whose father is a businessman well known for both his success and dishonesty. Mr. Wong faces increasing danger and is nearly executed himself as the investigation develops in treachery and complexity. As Mr. Wong follows the trail of dead bodies, he uncovers a jewel smuggling ring on the San Francisco waterfront and a case much larger than the death of a police officer.
A pretty Chinese woman, seeking help from San Francisco detective James Lee Wong, is killed by a poisoned dart in his front hall, having time only to scrawl "Captain J" on a sheet of paper. She proves to be Princess Lin Hwa, on a secret military mission for Chinese forces fighting the Japanese invasion. Mr. Wong finds two captains with the intial J in the case, neither being quite what he seems; there's fog on the waterfront and someone still has that poison-dart gun...
When an escaped circus gorilla appears to have gone on a murderous rampage, a threatened attorney calls on the detective trio of Garrity, Harrigan and Mullivan to act as bodyguards. In short order, we discover that there is more to the attorney than meets the eye, and the ape may be innocent after all. When a pretty young heiress faces peril, it's up to our heroic trio to save the day.
Captain Drummond and his girlfriend want to marry but a hidden treasure in the house in which they want to celebrate their marriage is complicating the situation involving a series of deaths and an elusive murderer.
While participating in a contest at a local newspaper in which school children are asked to submit a news story, local attorney Carson Drew's daughter Nancy intercepts a real story assignment. She "covers" the inquest of the death of a woman who was poisoned. Nancy doesn't think the young woman accused of the crime is guilty and corrals her neighbor Ted into searching for a vital piece of evidence and stumbles onto the identity of the real killer.
After committing a murder, Kay assumes a new identity and boards a ship. But, Kay is unaware that Sam, a skirt chasing detective, is following her and must outwit him to escape imprisonment.
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.
Drummond's wedding with Phyllis is interrupted when the inspector guarding their gifts is killed. He tries to trace the killers and uncovers the mystery of diamond counterfeiters.
Pepe Le Moko is a notorious thief, who escaped from France. Since his escape, Moko has become a resident and leader of the immense Casbah of Algiers. French officials arrive insisting on Pepe's capture are met with unfazed local detectives, led by Inspector Slimane, who are biding their time. Meanwhile, Pepe meets the beautiful Gaby, which arouses the jealousy of Ines.
Although Charlie and Lee are in Monaco for an art exhibit, they become caught up in a feud between rival financiers which involves the Chan's in a web of blackmail and murder.
Captain Drummond is travelling to Switzerland to marry his girlfriend. However, when a cargo containing dangerous explosives goes missing from its place, Drummond is forced to delay his plans.
When a young writer is falsely accused of murdering a famous actress, he escapes custody and joins forces with the daughter of a police constable to prove his innocence.