Leamas watches Karl Riemeck shot by East German guards at the Berlin Wall as Riemeck attempts to cross to the West.

Control offers Leamas a final mission to destroy East German spymaster Hans-Dieter Mundt before Leamas retires from the field.

Leamas stages a public decline as his operational cover, losing his position, drinking heavily, and destroying his professional reputation.

Leamas attacks a grocer who refuses him credit and is arrested, completing his cover as a fallen and disgraced ex-agent.

Released from prison, Leamas is approached in a park by a contact named Ashe, beginning his recruitment into the Communist network.

Leamas slips away from Ashe to meet Control privately at George Smiley's house and confirm the mission is proceeding.

Leamas travels to a hotel in the Netherlands with contact Kiever and begins a formal debriefing with Soviet officer Peters.

Leamas reveals the details of a secret British financing operation called Rolling Stone during his debriefing with Peters.

Leamas crosses the East German border and meets Fiedler, Mundt's Jewish deputy and most dangerous internal enemy.

Fiedler demonstrates that Rolling Stone bank withdrawals match Mundt's foreign travel dates exactly, making the case that Mundt is a British agent.

Mundt sends men to arrest both Fiedler and Leamas at the farmhouse before they can act on their evidence.

Fiedler opens the Party tribunal by presenting his full case that Mundt is a traitor who deserves death.

Mundt's representative produces Liz Gold as a surprise witness and uses her innocent testimony to discredit Fiedler's entire case.

Leamas stands up at the tribunal and confesses the full details of the British operation to the judges.

Leamas and Liz are shot by East German guards while attempting to climb the Berlin Wall to freedom.

Alec Leamas witnesses the death of his prize agent Karl Riemeck at the Berlin Wall and is immediately recruited by Control for one final mission: to destroy Hans-Dieter Mundt, the East German spymaster who dismantled his entire network. Leamas stages a deliberate fall from grace, ends up in prison, and is funnelled through a chain of Communist contacts to a Soviet debriefing in the Netherlands. Crossing into East Germany, Leamas works with Fiedler to build a case that Mundt is a British double agent, only for Mundt to have them both arrested before they can act. At a Party tribunal, Mundt's representative produces Leamas's lover Liz Gold as a surprise witness, and her innocent testimony collapses the case against Mundt entirely. Leamas confesses the full British operation to the tribunal, realising too late that he has been used as a pawn to protect Mundt all along. The novel ends at the Berlin Wall, where both Leamas and Liz are shot and killed by East German guards.

The mission to bring down Mundt and its devastating consequences.

Riemeck's lover crosses the checkpoint and warns Leamas that East German secret police have exposed the entire British spy network.

Control instructs Leamas to let it appear that the Circus has punished him harshly for the collapse of the Berlin network.

Leamas takes a job at a local library and meets Liz Gold, a young Communist Party member working in the archives.

Liz buys medicine and tends to the sick Leamas at his apartment every day while he refuses to speak of love.

Leamas says an unexpected goodbye to Liz the evening before he attacks the grocer and is arrested.

Leamas survives a group assault in prison by violently retaliating, driving a hoe handle into one attacker's stomach.

Kiever dismisses Ashe and makes Leamas a vague offer of generously paid work supplying information to foreign clients.

Peters informs Leamas that Riemeck's lover Elvira was found murdered in West Berlin after Riemeck's death at the checkpoint.

Two men posing as policemen visit Liz's apartment and reveal that Leamas named her as his next of kin.

George Smiley visits Liz, leaves his card, and promises that Leamas's friends will look after her financially.

Fiedler informs Leamas that Peters's promise of escape to Scandinavia was a lie designed to deliver Leamas into East Germany.

Leamas signs letters to European banks to determine whether the Rolling Stone accounts were ever actually withdrawn.

Liz receives a letter from the East German Communist Party offering her an all-expenses-paid exchange trip to Leipzig.

Liz is collected from a Leipzig Party branch meeting and driven to a special Praesidium gathering near the Polish border.

Mundt opens Liz's prison cell, checks the corridor is clear, and personally escorts her to a car waiting outside.

Before Leamas can begin his mission, his German spy network collapses when Riemeck's lover crosses the checkpoint with a warning, and Leamas must carefully construct a cover story of personal failure while also beginning an unplanned relationship with Liz Gold, a librarian and Communist Party member. His staged decline and imprisonment are watched from a distance by the Circus, and after his release Communist agents ferry him step by step toward the Netherlands, where he learns that Riemeck's lover Elvira has been murdered. In London, Liz is visited by men posing as police and later by George Smiley, who promises she will be looked after — foreshadowing how she will later be used. Back in England, Liz receives an improbable Party invitation to Leipzig, accepts it, and is eventually driven to the same tribunal that will decide Leamas's fate. The pool closes with Mundt personally escorting Liz from her prison cell to a waiting car, a small act of calculated mercy that serves no one's interests but his own.

The human cost behind the operation, from Liz Gold to the final crossing.

Control admits to Leamas that British Intelligence 'occasionally does very wicked things,' while insisting those actions are nonetheless justified.

Liz confesses to Leamas that she is a Communist Party member, and the two sleep together for the first time.

While Ashe is briefly absent during their dinner, Leamas slips away to call the Circus and report his location and plans.

Leamas describes to Peters how Rolling Stone funds were deposited abroad under false names for unidentified agents to collect.

Leamas suddenly recalls during Fiedler's interrogation that Peter Guillam accessed the Rolling Stone file despite it falling outside his remit.

Fiedler questions Leamas on outdoor walks about the moral foundations of Western espionage, clashing against his own communist convictions.

Fiedler concludes that Mundt deliberately kills anyone who knows too much about him, specifically to conceal his role as a double agent.

Liz accepts the East German Party's invitation to Leipzig, dismissing her own unease about the suspiciously flattering letter.

Mundt confronts the badly beaten Leamas in his cell and reveals he knows Leamas visited Smiley's house after first meeting Ashe.

Fiedler and Leamas, both beaten and imprisoned by Mundt, compare notes and agree they can still present the case against him.

Mundt's representative Karden recalls Leamas to the stand and forces him to confirm he was entirely without money, friends, or support.

Liz admits under tribunal questioning that Leamas promised she would be financially looked after before he was arrested.

The moment the tribunal verdict is delivered, Leamas looks into Mundt's eyes and instantly grasps the full extent of the British deception.

Leamas tells Liz in the car that Mundt is a British agent and the entire operation was designed to protect him.

Seeing Liz shot on the wall below him, Leamas climbs back down to her side rather than escape alone to the West.

From the moment Control admits that British Intelligence sometimes does 'very wicked things,' the novel traces a series of moral compromises and revelations that strip away every illusion its characters hold. Leamas maintains a secret line to the Circus even as he penetrates deeper into the Communist network, and his interrogations with Peters and Fiedler force him to produce truths — about Rolling Stone, about Mundt, about himself — that he does not fully understand. Fiedler's growing conviction that Mundt is a traitor, built through careful deduction and one decisive bank record, leads directly to their arrest and a tribunal that should have ended Mundt's career. Instead, Mundt's representative turns Leamas's emotional life against him, forcing Liz to inadvertently provide the evidence that destroys Fiedler's case and seals their fates. Leamas's recognition of the full deception — confirmed by a single look into Mundt's eyes — comes too late to save himself or Fiedler. His final act is to reject escape and climb back down the wall to Liz's side, the only choice left that is entirely his own.

The decisions, discoveries, and moral reckonings that shape the story's outcome.