Department S

A plane carrying the British diplomat Anthony Harvey explodes over the Channel. Although the passengers of a ferry witnessed the explosion, Sir Curtis is convinced that Harvey is actually still alive, so the the Department is tasked to find him.

Stewart and Annabelle talk to Harvey's landlady, and soon the agents come to share the suspicion that he staged his own death in order to assume a new identity, yet locating him proves far from easy. They also realize that Harvey may have worked for more than one side when they find themselves being shadowed by Russian agents. So now they are racing against time to find the man before the Russians do...