John Porter leads his unit into battle trying to rescue the CEO of a British weapons manufacturing company captured in Iraq, just before the invasion started. His team is joined by Hugh Collinson, operative of British military intelligence. The operation almost goes awry when Collinson kills larger portion of Porter's team, and blames a teenage suicide bomber, As'ad, Porter previously saved. The surviving members of the team manage to rescue their target, and Porter rejects Collinson's offer to joint Section 20, a new unit within military intelligence, doubting Collinson's account of the rescue operation incident and resigns from the SAS.

A sniper attempts to kill the President of Zimbabwe. Since there is evidence that the sniper could be British, Porter is sent in undercover to locate the sniper and silence him.