Episode 1

Madame Ostrakova, a Russian émigré, has been living in Paris for over twenty years. She is approached by a stranger while on her way home from work. He makes it clear that he knows about her chequered past and her reasons for leaving her home and her newborn baby daughter in the 1950s. He tells her that her daughter has had her own difficulties with the Soviet authorities, which may now be prepared to let her move to Paris. He instructs Ostrakova to go to the Russian embassy and collect passport photographs of the young woman and then to make a formal application through the French authorities.

Ostrakova asks a friend to contact General Vladimir, a former high-ranking officer in the Soviet army who defected to work for British Intelligence. Vladimir's lieutenant contacts her. Ostrakova tells him that the woman she saw in the photographs was not her real daughter. She also describes the man who contacted her. The lieutenant agrees to help and warns her that she is in great danger.

Now living in London, Vladimir receives a letter. He contacts Craven, a young trucker whose father was an old colleague of Vladimir's. Craven is sent to pick up a package in Hamburg, which is delivered by Vladimir's lieutenant. Ostrakova realises that she is being followed and quickly writes a detailed letter to Vladimir. Later, she is attacked by two men in the street and thrown in front of a speeding car.

Vladimir tries to get in touch with George Smiley, his last case officer at the British Secret Service, unaware that Smiley retired three years earlier. The call is taken by Mostyn, a young officer in the Service. He arranges to meet Vladimir at a safe house in Hampstead that evening.

Smiley is contacted when Vladimir's murdered body is found on Hampstead Heath, shot in the face at point blank range. Smiley liases with the police; the only clue is a receipt for a minicab ride. Smiley goes to the safe house and is asked by Oliver Lacon, a senior advisor to the Service from the Cabinet Office, to clear up the mess and keep the Service out of it. Mostyn later tells Smiley in confidence that Vladimir had said that he wished to speak to Smiley about 'The Sandman' and that he had 'two proofs'. Smiley agrees to take on the investigation and leaves the safe house.