When FBI agent Nick Davis (Viggo Mortensen) goes undercover to infiltrate the American arm of the Japanese mob (the Yakuza), he finds himself steadily rising through its ranks until he becomes a full-fledged member of the nefarious Tendo crime family. It's not long, however, before the Yakuza get involved in a dispute with an Italian mob leader (Michael Nouri), and the FBI is forced to step in. Davis must decide where his true loyalty lies.