The failure resulted in the dismissal of Control, Smiley, and allies such as Connie Sachs and Jerry Westerby, and their replacement by a new guard consisting of Percy Alleline, Toby Esterhase, Bill Haydon, and Roy Bland.

Tarr defends himself by explaining that he was informed of a Soviet mole at the highest level of the Circus – codenamed Gerald – by Irina, the wife of a trade delegate, while in Hong Kong.

Smiley is also given access to Circus documents, and begins by examining Alleline's restructuring, discovering the ousting of Jerry Westerby and Connie Sachs, as well as slush fund payments to Jim Prideaux.

Smiley visits Sachs, discovering that she confronted Alleline about her discovery that Polyakov was actually a Soviet Colonel called Gregor Viktorov, but he ordered her to drop the subject.

She also mentions rumours of a secret Soviet facility for training moles, and makes allusions to Prideaux and Bill Haydon's relationship being more than just platonic friendship.

Smiley also discovers that the log from the night Tarr reported in from Hong Kong has been removed, and Guillam starts to suffer from paranoia as a result of their operation.

Karla is believed to have followed his father into espionage, getting his start during the Spanish Civil War posing as a White Russian émigré in the forces of General Francisco Franco, recruiting foreign, mainly German, operatives.

Prideaux tells him Control believed there was a mole in the Circus, and had whittled it down to five men, Alleline (Tinker), Haydon (Tailor), Bland (Soldier), Esterhase (Poorman), and Smiley himself (Beggarman), and that his orders were to obtain the identity from a defector in Czech intelligence who knew.

He tells Smiley he almost didn't make the rendezvous with Max because he noticed he was being tailed, and that when he arrived to meet the defector, he was ambushed, taking two bullets to his right shoulder.

Prideaux suggests that the Czech defector was a plant, contrived by Karla to engineer Control's downfall through Testify's failure, all conceived to protect the mole.

[5] When Tinker Tailor Soldier Spy was published in 1974, revelations exposing the presence of Soviet double agents in Britain were still fresh in public memory.

[7] Senior SIS officer Kim Philby's defection to the USSR in 1963, and the consequent compromising of British agents, was a factor in the 1964 termination of Cornwell's intelligence career.

[8][9] Le Carré also drew from the paranoid atmosphere created by CIA counterintelligence chief James Jesus Angleton, who after Philby's defection became convinced that there were other moles operating at the highest levels of Western intelligence agencies.

"It's scarce wonder that Smiley has become almost as legendary a figure as [Kim] Philby, for Tinker, Tailor with all its outward verisimilitude, constructs a potent and appealing myth for the class-ridden and post-imperial angst of Britain in the 1970s."

[6] Mark Fisher said the notion of "postcolonial melancholia" hangs over the novel, arguing that both the protagonists and antagonists are motivated by what they see as Britain's "irreversible decline.

After his unmasking and capture, Haydon voices both a latent hostility towards the United States and a mourning of Britain's lack of "relevance or moral viability in world affairs.

Melvyn Bragg wrote that le Carré sought to illustrate that "the public or institutional default is always more excusable than the personal betrayal of faith.

[11]Tom Maddox wrote that Smiley's conflict with the Circus, past and present, represents the idealistic virtues of the Second World War that are "at odds" with the inhumanity, sophistry, and careerism of the spying profession.

The part of Moscow Centre most often referred to in Le Carré's novels is the fictional Thirteenth Directorate headed by Karla, the code name for a case officer who has risen and fallen from political favour several times and was at one point "blown" by the British in the 1950s.

"[3] John Powers of NPR has called it the greatest spy story ever told, noting that it "offers the seductive fantasy of entering a secret world, one imagined with alluring richness.

The series was directed by John Irvin, produced by Jonathan Powell, and stars Alec Guinness as George Smiley, with Ian Richardson as Bill Haydon.

In 1988, BBC Radio 4 broadcast a dramatisation, by Rene Basilico, of Tinker Tailor Soldier Spy in seven weekly half-hour episodes, produced by John Fawcett-Wilson.

It includes a cameo appearance by Le Carré in the Christmas party scene as the older man in the grey suit who stands suddenly to sing the Soviet anthem.

The film also stars Colin Firth as Bill Haydon, Benedict Cumberbatch as Peter Guillam, Tom Hardy as Ricki Tarr, and Mark Strong as Jim Prideaux.