Roger Allam

self (narrator)

Annie Machon

Self - Former MI5 intelligence officer

Ben Macintyre

Self - Author of A Spy Among Friends: Kim Philby and the Great Betrayal

Dr. Helen Fry

Self - British Intelligence historian

Dita Gjuraj

Self

Tom Bower

Self

Roland Philipps

Self - Author of 'A Spy Named Orphan: The Enigma of Donald Maclean'

James P. Olsen

Self - Former Chief of Counterintelligence at the CIA

Miranda Carter

Self - Author of 'Anthony Blunt: His Lives'

Mikhail Petrovich Lyubimov

Self - Former KGB colonel

David Haig Thomas

Self (archive footage)

Adolf Hitler

Self (archive footage)

Harold Rickett

Self (archive footage)

Joseph Stalin

Self (archive footage)

J. Edgar Hoover

Self (archive footage)

Kim Philby

Self (archive footage)

Guy Burgess

Self (archive footage)

Anthony Blunt

Self (archive footage)

Margaret Thatcher

Self (archive footage)