Shiro, son of the aging boss of the Yakuza crime syndicate, ascends to power with the help of a duplicitous Lei, and vows revenge on Section 20 for his father's murder. With the location of his latest Bangkok crib compromised again, Locke suspects there's a second North Korean spy in town. Stonebridge, Richmond, Martinez and Locke fend off waves of attack from the Yakuza, while Scott finds his long-anticipated visit with son Finn less than idyllic. After its latest bloody face-off, Section 20 heads to a private island, desperate to learn what the Yakuza have that the North Koreans covet.