Part 3

The midpoint of the serial stops moving forward and turns back into Smiley's own professional past. The bill for the night sets the business plainly: Vladimir had two proofs and Smiley found only one, a photograph of erotic content in which he recognised Otto Leipzig, the General's lieutenant, and having learned that the General quarrelled with his postman, Hector, he plans to visit some old friends from Circus days.

The first is Toby Esterhase, formerly of the Lamplighter section, now a dealer in pictures in a Bond Street gallery. He is the postman who carried messages to Vladimir and who, when the rain came, took away the umbrella. He tells Smiley what he has told nobody else: that the General came to him about two weeks before his death and asked him to collect a document. He speaks slightingly of Vladimir and of Leipzig, a pedlar whose material he regards as largely invented, and Smiley reminds him that Leipzig's reporting on Moscow Centre was usually first-rate.

The second visit is the one the serial is judged by after Guinness. Smiley drives into Oxfordshire to see Connie Sachs, the Circus's retired Russia analyst, who is dying in her dacha and cared for by her former colleague and companion Hilary. He has come for her memory, not her files, and she gives him the two identifications the case now needs. The first is Oleg Kirov, the ginger-haired Soviet officer, the Ginger Pig in Leipzig's phrase, whom Leipzig knew as a student and who was informing on radical students before he was known to be an agent. The second, and the one that matters, is the long-standing rumour that Karla has a daughter.

The part then leaves England. Smiley flies to Hamburg, checks where Villem Craven caught the ferry, finds the Blue Diamond, the club in which the photograph was taken, pays for membership and waits there for its owner, Claus Kretzschmar, Leipzig's old associate and the man the Circus has always used when it needed to reach him. The hour ends with Smiley pressing him: "But you do have an address where I can find him."

Beryl Reid's Connie Sachs is the performance the whole serial is judged by after Guinness's, and it won her the 1983 BAFTA for Best Actress. What she plays is a woman the service has used up and who still gives it what it wants, and it is the only sequence in the serial in which Smiley is the one asking for something and has no leverage at all. Her line, give it up, George, it's grey, half-devils against half-angels, nobody knows who the goodies are, is where the serial's moral position is usually quoted from. Bernard Hepton's Esterhase is her counterpart: an operator who has survived by being useful to everybody and loyal to nobody, and who is visibly pleased to be back in the field.

The weakness is that the hour is exposition delivered in conversation, and the Hamburg strand feels bolted onto the end of it. A viewer who wants the plot to move will find this the slowest of the six. But it is also the only part of the serial with no crime in it at all, two conversations and a reconnaissance, and the only one whose best scene takes place in a garden in Oxfordshire. It sits at the exact middle, where the cost of the whole enterprise stops being institutional and becomes personal, and it is one of the three parts the site holds up as the serial's must-see.