President Chester Arthur calls semi-retired Murphy back to duty when, with a pending meeting of world leaders in New York City, prostitutes are being murdered and dismembered in the streets. Arthur's special assistant William Burke travels to New York with Murphy where Murphy is given authorization to take command of the investigation. So important is the meeting with world leaders to Arthur that he calls upon the services of the Pinkerton Detective Agency to assist Murphy.

Murphy finds himself saddled with a diminutive Pinkerton's Detective named Melvin Knoop. From Scotland, he's...