Once a wealthy man, John Pollard now resides in reduced circumstances in Washington, D.C. with his pretty daughter Polly. Despite the poor conditions, Polly manages to move in good social circles and meets multimillionaire George Singleton and Lieutenant Richard Travers, at the home of Mrs. Madison Derwent. Also at the Derwent mansion is Baron Wootchi, a Japanese diplomat trying to obtain valuable plans that are in Travers' possession. Old Pollard owes Singleton money and tries to persuade his daughter to marry the millionaire. Polly refuses and accepts Travers' proposal instead, until her father informs her that Singleton can seize their house unless Polly pays off the debt by becoming his wife. Meanwhile the Baron offers Pollard $50,000 to produce the documents in Travers' keeping. Pollard steals the papers and goes to a roadhouse to turn them over to the Baron. Discovering the theft, Polly follows and confronts the Baron at gunpoint.
A $5,000 wager is made between two prominent jewelers, Mr. Thorpe and Mr. Chandler, as to whether their most valuable jewels can be stolen. Thorpe, seeking to stack the odds in his favor, asks Police Commissioner James Stone, a business crony, to enlist the help of Diamond Daisy, a jewel thief who is trying to go straight. Posing as a rich heiress, she asks Mr. Thorpe to accompany her to show her father an expensive item of jewelry. Instead, Mr. Thorpe is detained in an insane asylum by a doctor who has been led to believe that Thorpe is Daisy's insane husband. Daisy absconds with the jewels, but a vindictive detective, who has been following Daisy, thinks the heist is for real and tries to arrest her. Eventually the commissioner intervenes and all ends well.