After attending a medical conference in Beijing and coming frighteningly close to dying in a car crash, Dr Matthew Nolan (Richard Armitage) arrives home and is immediately arrested at Londons Heathrow Airport.

Exhausted and confused, Nolan is accused of the murder of a woman who was in the car he crashed. Despite his protests that he was driving alone, Nolan is set to return to China to face charges.

DC Hana Li (Jing Lusi) is the no-nonsense officer charged with accompanying Nolan back to Beijing. However, in flight, when a first death occurs, DC Li begins to suspect foul play. Further deaths confirm that Nolan is in danger, and after a call from MI5, Hana finds herself embroiled in an escalating conspiracy that seems to implicate both China and people in her own government.