Planted in a Tokyo crime syndicate, a U.S. Army Investigator attempts to probe the coinciding death of a fellow Army official.
In Tokyo, a ruthless gang starts holding up U.S. ammunition trains, prepared to kill any of their own members wounded during a robbery. Down-at-heel ex-serviceman Eddie Spannier arrives from the States, apparently at the invitation of one such unfortunate. But Eddie isn't quite what he seems as he manages to make contact with Sandy Dawson, who is obviously running some sort of big operation, and his plan is helped by acquaintance with Mariko, the secret Japanese wife of the dead American.—Jeremy Perkins {J-26}
During World War 2 a group of criminals robs trains of Army ammunition that ends up being used in other robberies. When an American is shot during one robbery a group of Army Inspectors get to him before he dies and get information about the gang he was with. After discovering that many American crooks in the area have been killed with the same gun, Eddie Kenner (Robert Stack) goes undercover as Eddie Spanier to get information on a local American gangster Sandy Dawson (Robert Ryan). Sandy is an all-business gangster who runs his gang like an Army platoon referring to crime jobs in language that recalls his days as a soldier. Sandy also kills any of his crew who is wounded so as not to slow down his gang and to prevent the police from getting a living prisoner who can inform on the criminal gang. As Eddie moves closer to the gang he gets more information from Mariko (Shirley Yamaguchi) as her American husband was killed by Sandy's gang. Eddie and Mariko fall in love as she learns his real motive for working with Sandy, and she takes steps to help him by delivering information to Eddie's partner Capt. Hanson (Brad Dexter), and Inspector Kito (Sessue Hayakawa) who are keeping Sandy under surveillance. When a big job goes awry Sandy believes that the leak comes from Griff (Cameron Mitchell) his second in command who was jealous over the inclusion of Eddie in the gang. When Sandy kills Griff he realizes from his inside source at the police department that Eddies is actually the spy and maneuvers him into a robbery to kill him.
