In England in 1963, Nicholas Elliott works for MI6 but is left in turmoil when he learns his close friend and colleague Kim Philby had been secretly working as a double agent for the KGB and has defected to the Soviet Union.
Cast:Guy Pearce , Damian Lewis , Anna Maxwell Martin , Adrian Edmondson , Stephen Kunken , Monika Gossmann , Nicholas Rowe , Lucy Russell , Lucy Akhurst , Puiu Mircea Lascus , Jennifer Marsala , Alexander Terentyev , Anastasia Hille , Karel Roden , Gershwyn Eustache Jnr , Gilly Gilchrist , Alex Price , Steven Elder
In the wake of Kim Philby's escape to Moscow, his closest friend in MI6 is under investigation by Lily.
Investigator Lily Thomas tries to get Elliott to reveal what he knows about Philby. She uses psychological tricks to steer him in the right direction.
Philby begins to understand that the KGB can never fully trust him now that he is in Moscow, and as far as they're concerned, his life as a spy for them is over; in London, Elliot warns Anthony Blunt that his cover has been blown.
Elliott rattles Blunt's cage to make him panic and then follows him to a clandestine meeting in the middle of the night.
Elliott and Lily fear that no one can really be trusted and race to interrogate Blunt. However, Angleton thwarts their plans because he wants Blunt arrested.
Lily has forced Elliot to remember more than he perhaps ever wanted to about Philby. Months later, Elliott receives a letter from Philby asking for a meeting in an East Berlin bar.