The Duplicated Man Department S : Season 2 Episode 9

An aeroplane carrying MI5 agent Anthony James Harvey explodes over the English Channel and eye witnesses claim that nobody could have survived. However, evidence washed up on the Kent coast leads Sir Curtis to believe that Harvey actually parachuted from the plane before the explosion and staged his own death. He is a double agent who has been working for the Russians and has spent years creating a new identity to escape his masters. As the Department 'S' team go to interview Harvey's mother and associates they are observed and pursued by Russian agents.