When Harry Mackintosh is called upon to exfiltrate a valuable asset from East to West Berlin, what could have been an intelligence coup becomes an international embarrassment. Mackintosh’s men and his lover are killed by the East German secret police in a brutal crossfire and he barely escapes with his life. He flees to the West and promises himself that he will have vengeance. Mackintosh is the head of Berlin Station but he doesn’t have the staff to compete with the Stasi. He returns to London to plead for the resources to fight back. But instead of the seasoned operatives that he needs, Mackintosh is given a single man: Jimmy Walker, a petty criminal with a record for robbing banks.