Trevor Phillips is a young barrister determined to avenge the murder of his brother Arthur. When he discovers that an old friend, Rodney Fraser, is a member of the masked gang responsible for the murder, with Fraser's assistance he finds the killer, who turns out to be his fiancée's uncle.
Young detective Hobart tracks down the headquarters of a gang of blackmailers, surveils them from the empty house opposite. He is trapped by the gang, but escapes during a fire.
Richard Fordyce, released from prison after serving a sentence for a counterfeiting – a crime he didn’t commit – is anxious to find out who framed him. Traveling penniless across the country, he holds an auction for his services and is "purchased" for £5 by Margaret Fenton. Margaret’s husband, Claude, turns out to be the man who framed him.
A captain begins blackmailing a wealthy family. He is found dead, and the wealthy family is caught up in the ensuing investigation of his death. Each member is pitted against each other to prove innocence.
Frances Dayton, a starving young woman, is rescued from a suicide attempt in the Thames by a solicitor who plans to use her as a co-respondent in a divorce case for his client, Captain Leslie Fairbrother. Many years later, Frances is now managing director at a London department store. On the verge of marrying her employer’s son, she is called upon to cast a vote regarding the funding of a large exploration scheme.
As described in a film magazine, the dogged determination and big heart of an Irish patrolman prove victorious in his lone battle for love and honor. John Francis Foley (Rawlinson), known as "Jack 0' Clubs," has managed by daring and fistic prowess to gain the respect of the hardened characters of his beat on the East Side of New York. Tillie Miller (Dwyer), a little café singer, attracts him.
Having suffered shell shock during the World War I, Stephen Ronsart, a distinguished engineer and explosives expert, develops a Jekyll and Hyde-like split personality. His darker alter ego manifests a sinister obsession, causing a series of catastrophic train crashes that baffle the police and bring the railway to a virtual standstill. In a cruel twist of fast, the authorities enlist Ronsart himself to thwart the saboteur's reign of terror, and he invents an invisible ray designed to protect the trains from danger.
Harry Newman is engaged to Lady Violet. Corry, jealous of Newman, pays nightclub singer Mabel to flirt with Newman and blackmail his father over letters she claims to have written to his son.
On an ocean crossing, lawyer Steven Kennedy repeatedly proposes marriage to Joan Manners, eventually she accepts. She hits it off well with Steve's daughter Connie, but find that she is in a relationship with Schuyler Durkin, who Joan had once also been in a relationship with.
Broadcaster Gilbert Harding, playing a crime reporter, explains the behind-the-scenes work of Scotland Yard, as detectives investigate the theft of a lorry, which results in a conviction for murder.
Mr Carruthers is on holiday on the Riviera, with his wife and son Jack. He becomes infatuated with Mrs. Oliver, an adventuress, who is posing as a widow.
Criminals Dushka Vernon and Flash Gerald decide to swindle elderly sweet shop owner Mrs Deeping, living in a country village, out of her money by producing her "long-lost son" who is really "The Babe", one of their gang, just released from prison. However, once he takes up his disguise he begins to become entranced with the quiet country village and falls in love with the vicar's daughter. He ends up refusing to help his former criminal associates and reveals his true identity to the villagers.
Dr. Bevan persuades unreputable character Lee MacArthur to stage, in his country house, a mystery play he has written. During a rehearsal, McArthur is killed, and most of the people present are suspected of the crime.