On Her Majesty's Secret Service recap

While hunting the vanished SPECTRE chief Ernst Stavro Blofeld, James Bond meets Teresa di Vicenzo, known as Tracy, and prevents her suicide. Her father, crime leader Marc-Ange Draco, offers Bond money to marry her; Bond refuses the bargain but accepts Draco's intelligence on Blofeld, while his feelings for Tracy deepen independently. A heraldic inquiry lets Bond enter Blofeld's Alpine clinic at Piz Gloria disguised as Sir Hilary Bray. He learns that Blofeld is hypnotizing young British women and sending them home to spread agents that will destroy crops and livestock. Bond escapes the mountain, is rescued by Tracy, and proposes to her. He returns with Draco's men, wrecks the laboratory, and foils the plot, though Blofeld escapes. Bond and Tracy marry. Minutes later Blofeld and Irma Bunt attack their car, killing Tracy and leaving Bond alive beside his new wife's body.

SPECTRE attempted to extort the Western powers with stolen nuclear weapons in Thunderball. Bond and allied forces recovered the bombs and defeated Emilio Largo's field team, but SPECTRE founder Ernst Stavro Blofeld remained beyond the final battle and escaped. Bond has since been assigned to find him, an investigation that has produced little progress and has become a source of deep frustration.

On the French coast, Bond notices Teresa di Vicenzo, called Tracy, driving recklessly and later moving toward the sea in an apparent suicide attempt. He intervenes before the police arrive. At a casino he covers a gambling debt she cannot pay, and the two spend the night together, but her despair remains evident. Men then seize Bond and take him to Marc-Ange Draco, Tracy's father and the head of the Union Corse. Draco explains that his daughter has been shattered by a failed marriage and the death of her child. He believes Bond could restore her desire to live.

Draco offers Bond a large dowry to marry Tracy. Bond refuses to treat marriage as a purchase, although he agrees to see her again and is already moved by her. In exchange for useful information, he asks Draco for help locating Blofeld. Draco's contacts point toward Switzerland. Bond returns to London still angry at the stale official search and prepares to resign, but M redirects his energy when the College of Arms reports that a man in Switzerland is seeking recognition as the Comte de Bleuville. A physical detail in the correspondence suggests that the claimant may be Blofeld.

The Secret Service arranges for Bond to impersonate heraldic expert Sir Hilary Bray. He travels to Piz Gloria, an isolated clinic and research station high in the Swiss Alps, where the supposed count is pursuing both a noble title and medical work. Irma Bunt manages the establishment and supervises a group of young British women being treated for food allergies. Bond meets the claimant under his adopted identity and maintains the genealogical cover while studying the clinic. Its isolation, communications, guards, and strict routines make clear that leaving with evidence will be harder than entering.

Bond becomes close to Ruby Windsor and learns that the patients receive nightly instructions while in a suggestible state. Their supposedly curative treatment is actually preparing them to carry biological agents back to farms across Britain, where they can devastate agriculture. Bond confirms that the clinic's director is Blofeld and tries to pass information to outside support. Local agent Shaun Campbell is caught, and the clinic's security links him to Bond's cover. With his identity collapsing and the germ-warfare plan near completion, Bond must escape Piz Gloria without waiting for an official extraction.

Bond escapes on skis and is hunted down the mountain through darkness, snow, and a holiday crowd. Exhausted and nearly trapped, he encounters Tracy, who has come looking for him. Her driving carries them through further pursuit and out of immediate danger. During the escape Bond recognizes that his attachment to her is not gratitude or an extension of Draco's proposal. He asks Tracy to marry him, and she accepts. After reaching safety, Bond reports Blofeld's biological plan and begins arranging both a strike on Piz Gloria and a life with Tracy beyond the operation.

Bond enlists Draco and Union Corse fighters for a helicopter assault on Piz Gloria before the treated patients can disperse as carriers. Using deception to approach the mountain, the force attacks the clinic, frees the women, and destroys the facilities supporting Blofeld's agricultural warfare scheme. Blofeld escapes during the raid. Bond pursues him into a bobsleigh run, but the dangerous descent ends with Blofeld getting away. The immediate plot is broken and Bond survives, yet his principal enemy remains at large as preparations for Bond and Tracy's wedding continue.

Bond and Tracy marry and leave together by car, looking toward a shared future after the violence surrounding Piz Gloria. On the road a second car approaches, driven by Blofeld with Irma Bunt as passenger. Bunt fires into the newlyweds' vehicle and they escape before Bond can respond. Bond is unharmed, but Tracy has been shot dead only minutes after the ceremony. A policeman finds Bond holding her and speaking as if she were only resting. Blofeld is still free, the victory over his project has become personally meaningless, and the book ends at the point of Bond's shock and denial beside his wife's body.

Bond returns to Piz Gloria with Draco and Union Corse men in a helicopter assault disguised as a rescue operation. They destroy Blofeld's biological-warfare base and free the women being used as unwitting carriers, but Blofeld escapes. Bond pursues him down the mountain in a bobsleigh run; the chase ends without Bond capturing or killing him. Bond and Tracy nevertheless proceed with their marriage, surrounded by friends before leaving for their honeymoon. On the road, a car driven by Blofeld draws alongside. Irma Bunt fires into Bond's car and the attackers speed away. Bond survives, but Tracy is shot dead only minutes after the wedding. When a policeman arrives, Bond remains beside her and speaks as though she is merely resting, unable to accept what has happened. The book closes at this moment, with the promise of their future destroyed and Blofeld still free. Tracy's murder becomes the premise of Bond's condition in the next novel.