Young Edyth Vail, believes her fiancé Allen Morris may have committed a murder, asking Ashton Kirk to investigate the crime. The fiancé admits he went to the David Hume's home to retrieve plans for a submarine, invented by his scientist father and stolen by the murdered man, but Allen claims he left the home before retrieving the plans. Kirk uses a train conductor's punch ticket to discover the identity of the murderers, one of whom is mute, and sets a trap to apprehend the suspects.
Four wealthy young men, Larry Van Cortlandt, Castleton, "Fatty" Harriman and Payne, become intoxicated in a cabaret where munitions maker Stanhope Shelton is giving a party for his daughter Natalie. Larry is attracted to Natalie, but he is ejected with his friends before he can secure an introduction. Plainclothes detective Hogan vows to capture Larry, who seeks asylum on his yacht with his friends. After the crew quits, Larry and his friends handle the boat. The next morning Castleton and Payne place a "for hire" sign on the boat and the Sheltons engage it. Larry teaches Natalie to steer and runs into several boats in the process. Four people in the Shelton party turn out to be burglars and rob the other guests. Meanwhile two other crooks rob the Shelton mansion. Larry manages to capture all the crooks at the Shelton home, and he wins over both Natalie and her father.
Penniless aristocrat Yvonne Dupré ekes out a living selling her paintings to a crooked dealer, Leon Naisson, who passes them off as other more famous artists. Leon confides to his unscrupulous model Romildo, that he is attracted to Yvonne. Romildo drugs his lover, fiery Apache dancer Juliette who closely resembles Yvonne, then tries to extort money from Leon to have his way with her. Leon discovers the duplicity but convinces the artist's sweetheart, Dick Gray, that she has been unfaithful. As police close in on Leon, he frames Yvonne by planting forged paintings in her studio. Following Yvonne's arrest, Juliette is informed by her foster sister that she was stolen by gypsies as a child and is actually Yvonne's twin sister. Juliette exposes Leon's operation to the police, reuniting Yvonne and Dick.
On the trail of counterfeiters Detective Craig is on their trail. Suspicion falls on James Dalton who passes bad money through unsuspecting "fences." Dalton plants bad bills on young Bob Brierly and when it is detected Dalton, as usual, escapes while the innocent Bob is caught and convicted. Upon his release Bob meets Mae Edwards who gets him a job in her bank. When Dalton comes to the bank to case it for a robbery he runs into Bob and tries to recruit him as an accomplice. Bob, who has married Mae, refuses. Dalton causes him to lose his position and because of Dalton’s persistent efforts forces Bob to join the crook. Craig, shadowing Dalton, knows Bob is taking part against his will. Craig foils the robbery and after a motorboat chase Dalton is captured and exonerates Bob.
Millionaire Joshua Barker insists that his daughter, Faith, must marry Phil Langhorne, a man that neither likes, and Faith is in love with and eager to marry her childhood sweetheart, John Temple.
A boxer saves a girl from a noble kidnapper.
Humanitarian Roberta induces her father to hire former convict, Bill, as his gardener. When she leaves on vacation, Bill steals her jewelry and eventually sells a brooch to her boyfriend, Richard, who unknowingly gives it to her as a present.
Orphan, Audrey Bedford takes the blame for her half- sister's gem theft and later exposes her employer as her crooked husband.
Bob Marston, a San Francisco socialite turned amateur detective is assigned to apprehend a gang of bootleggers.
In Africa a typist is framed for killing a diamond smuggler who betrayed her father.
A tramp is hired to pose as a financier to obtain a Balkan radium concession.
The Charlatan
Secret of St. Job Forest
Wade Hildreth is sent to New York from London to receive a diamond necklace for Lady Gwendolyn from the jeweler Arabin. A gang of crooks led by Pete Fielding, known as "The Shadow," plans to keep Hildreth from going to Arabin's until they have robbed the store. Actress Morn Light, whom the Shadow loves, agrees to entice Hildreth to her apartment to be imprisoned. When she warns Hildreth because she wants to avenge her father's death, which was caused by the Shadow, the Shadow overhears and captures them both.
A usurer cancels a woman's debt in return for wresting a financial secret from a minister's wife.
A reporter and a detective team up to solve the murder of a nightclub singer who had been involved in a divorce scandal.
Winthrop Clavering a mystery writer, is continually ridiculed for the fiction of the crimes he depicts, so he decides to solve a case himself. To that end, he determines to find the slayer of Pedro Alvarez, who whispered before dying that his assailant was a woman. At the City Refuge for Homeless Girls, Clavering obtains the assistance of Margaret Holt, the sister of Victor Holt, the district attorney. Margaret, it is revealed, was abducted by Juanita, a member of a gang of white slavers led by Alvarez. After escaping from a brothel, Margaret became Alvarez' stenographer, hoping to gather secret information on his gang. While searching for evidence, Margaret was surprised by Alvarez, whom she killed. Finally, Clavering captures the gang, clears Margaret, and encourages her romance with cub reporter Jack Howell. This film is presumably lost.
A blackmailed ex-thief is executed for a murder he didn't commit.
The husband of Mrs, Cranston is in tight quarters. He is caught both "short" in funds and in stock. In order that he may be able to cover up his margins, he decides to rob his wife's jewels. He plans to do so, but his wife anticipates him and steals the jewels herself, she having reason to believe that he would attempt the crime in a moment of weakness. The husband, when he finds that his wife's jewels are missing, raises a "hue and cry," and the police take up the case. After considerable investigation, the crime is traced to Mrs. Cranston.
A detective saves his boy assistant from a bank swindler after escaping a fire by overhead cable.