Frank and Joe Hardy become involved in a case affecting national security when Joe dials a wrong telephone number and gets the Pentagon. Two words--"Bombay Boomerang"--that the boys hear before the line goes dead plunge them into a whirlpool of danger and intrigue. In a race against time the three Hardys foil a diabolical scheme to create widespread havoc in the United States. Pulse-pounding excitement fills every page of this suspense thriller.