Based on Chris Ryan's best-selling novel, "Strike Back" is the high octane, action-fuelled story of section 20, an elite special forces unit carrying out high-risk military missions across the globe. From the tropical beaches of Thailand to the towering peaks of the Swiss Alps, 'Strike Back: Legacy' thrusts Section 20 onto a mission the scale of which has never been seen before as this season Scott and Stonebridge go up against the state sanctioned criminal wing of the North Korean regime, known as Office 39. Coordinated by a beautiful and devoted North Korean agent deeply embedded in the British Establishment, Han Li-na (Michelle Yeoh) is secretly assembling intercontinental ballistic missiles capable of wiping out Washington and London. Putting a stop to the threat posed by North Korea becomes Section 20's undoing when, in a bid to ease escalating global tensions, Sir Charles Ridley (James Wilby) a senior figure within Whitehall, brokers a deal with North Korea to eliminate Section 20. In a heart-breaking and chilling season finale, Scott and Stonebridge - desperate and on the run - are chased down by ruthless mercenaries employed by the one enemy they know they can never beat - their own government.