Lea Anderson is a soldier in the British Special Forces, but has now come to doubt her choice of career. The secrecy, bloodshed and lack of a normal life are too much for the young woman who finally decides to call it quits – but not before going on one more mission in the Middle East to make sure her team and her stepbrother Paul get through it safely. When their unit runs into an ambush set by the terrorist they are supposed to kill, Lea and Paul get captured and forced to make a life-and-death decision: one of them will get to leave, one of them will die. In a moment of weakness, Paul bails and Lea is now left in the terrorist's hands, sure to face her maker. Years later, she returns to the UK. Not as a former hostage, but as a soldier, fighting the establishment that made her who she now is – a highly trained avenging angel.