Set in Berlin in 1989, shortly before the collapse of the Berlin Wall, we find an MI6 agent named Lorraine Broughton on a mission to try to get a much sought after highly classified list of spies working for Western agencies around the world, kept hidden within the case of a luxury watch, in order to prevent it from going to the KGB. Operating in flashbacks as the bruised and fatigued agent divulges the details of her botched mission to her immediate superior, as well as to a bigwig in the CIA, we learn of her covert mission to acquire the list, initially assigned to work with the chief operator in Berlin, David Percival. In the meantime, they must contend with dangerous Soviet operatives, the East German military, Stasi officers, and an unknown double agent working both sides of the Wall.