Book excerpt: Presents the results of a review of DHS¿s handling of suspicious passengers and activities aboard Northwest Airlines Flight 327 from Detroit to L.A. on June 29, 2004. On this flight, 13 Middle Eastern men behaved in a suspicious manner that aroused the attention and concern of the flight attendants, passengers, air marshals, and pilots. The objectives of this review were to: (1) determine the specific circumstances relating to Flight 327, including DHS¿s handling of the suspicious passengers before boarding, during flight, and after the plane landed; and (2) identify any lessons learned as a result of the suspicious incident. The auditor interviewed officials of various Fed. agencies, 4 major airlines, 10 airline industry assoc., and 6 passengers. Illus.