Erick Strong is an assassin, whose attempts to settle down into a normal life have been scuppered. It's not just his old career that makes Erick different from everybody else, though. He's biologically different - his mother injected herself with an advanced serum that made her twin children immune to any chemical weaponry. In this, the final installment of the trilogy, Erick must wrestle with his own insecurities and the emotions that leave him vulnerable, while he tries to stop a psychopath, Paris, from gaining information about his unusual and valuable DNA make-up. After Erick is involved in a gunfight at a London warehouse, the officers of the Metropolitan Police are becoming involved in a case that's going to take them in way over their heads. Bela, is still seeking her own revenge and this time, she's determined to get it.