Pledging to revenge the execution of his brother, whom the District Attorney caused to be convicted, Richard Allen, a quaint individual who takes delight in concealing his identity by playing the role of a valet to an extravagant young man in New York, plots for the downfall of the prosecutor and educates his cleverest female crook, "Three-Arm Fanny," with a view to having her fascinate and marry the District Attorney. The "Master Mind," under various disguises, informs the District Attorney that he will receive the four aces at certain intervals and when he receives the ace of spades, the end will be near.