Between August 1937 and December 1941, terrorist wars broke out between Nationalist secret agents and the assassins of the Japanese military authorities who occupied most of Shanghai, and a spate of assassinations, bombings, and machine gun raids took place under the very noses of authorities. The release of secret Chinese police files by the C.I.A. allow the inner workings of these terrorist groups, and their links to the Green Gang just before Pearl Harbor was bombed and World War II erupted, to be exposed for the first time.