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.