September 1945. Japan has just capitulated, and World War Two is official over. Buck, Tumb and Sonny find themselves on a flight to Tokyo where they are to receive a well-deserved medal. But while the Emperor himself ordered his country to surrender, there are still die-hards in the Japanese military determined to continue fighting. Among them, members of the terrifying Unit 731, guilty of horrific war crimes and specialists in bacteriological warfare - among other things ...