The final novel in the Witcher Saga weaves together multiple timelines and frame narratives to conclude the story of Geralt of Rivia, a professional monster hunter known as a witcher, the sorceress Yennefer, and their adopted daughter Ciri.
The novel opens with a frame story set in a world resembling Arthurian Britain. Ciri, a young woman with ashen hair and a scar on her cheek, encounters Galahad, a knight of King Arthur, beside an enchanted lake. She explains she comes from another world, carried through fog by boat, and agrees to tell her story, invoking the serpent Ouroboros, a symbol that past, present, and future are contained in every moment. A second frame narrative, set many years later, follows Condwiramurs Tilly, a young dream-reader, and the sorceress Nimue, who together use prophetic dreams and artifacts to reconstruct the legend of Geralt and Ciri. Their recurring analyses of dreams provide a structural device that frames and comments upon the main narrative.
Meanwhile, Yennefer languishes in the dungeon of the renegade sorcerer Vilgefortz, weakened by dimeritium shackles that suppress her magic. Vilgefortz taunts her with false claims that Geralt and Ciri are dead. The bounty hunter Bonhart, who boasts of having captured Ciri and killed three witchers, visits Yennefer's cell and attempts to assault her. Yennefer fights back savagely, establishing both her unbroken spirit and Bonhart's sadism.
The main story picks up with Geralt wintering in Toussaint, a fairy-tale duchy famous for its wines. He arrived the previous autumn with his traveling company: the vampire Regis, the archer Milva, the young knight Cahir from the southern empire of Nilfgaard, and the spirited young woman Angoulême. At Beauclair Palace, Duchess Anna Henrietta welcomes them. Geralt's friend the poet Dandelion has become the duchess's lover and decides to stay permanently. Geralt begins a passionate affair with Fringilla Vigo, a sorceress and the duchess's kinswoman, who heals his injured knee, provides a protective amulet, and shares crucial knowledge about Ciri's bloodline.
Fringilla is secretly reporting to the Lodge of Sorceresses, a clandestine council of powerful women who shape political events. The Lodge tasks her with keeping Geralt in Toussaint and extracting the location of Vilgefortz's hideout. Geralt's departure is triggered when he overhears Nilfgaardian nobles plotting to assassinate Emperor Emhyr var Emreis, using the imprisoned Yennefer as a magically controlled assassin. During an emotional farewell, Fringilla extracts the hideout's name, but Geralt has deliberately given her false information. The Lodge's strike force raids the castle called Rhys-Rhun and finds it abandoned for decades.
Parallel to Geralt's story, Ciri is trapped in the world of the Aen Elle, elves who inhabit another dimension. The Aen Elle sage Avallac'h explains that Ciri carries the Elder Blood, a gene constructed by elven sorcerers, and the elves want her to bear a child with their ancient king, Auberon Muircetach, to produce an heir capable of opening a permanent gateway between worlds. Ciri reluctantly agrees after failed escape attempts, but her encounters with Auberon end in repeated failure. She discovers that the Aen Elle conquered this world and enslaved its human inhabitants. An alliance with unicorns, led by one called Ihuarraquax, reveals a ravine of human skulls proving the elves' genocide. The unicorns teach Ciri to harness her power over time and space. On her last night, Ciri finds Auberon dying from an overdose of a stimulant contained in a flacon provided by the elf commander Eredin Bréacc Glas; whether Auberon took it himself or Eredin administered it remains unclear. Escaping by boat, Ciri fights Eredin, stabs him, and flees with Ihuarraquax into interdimensional travel.
Ciri's odyssey takes her through dozens of worlds, pursued by Eredin's elite cavalry, the Red Riders. Nimue and Condwiramurs, working from their tower, use magic and dream-reading to guide Ciri toward her destination: Stygga Castle, Vilgefortz's true hideout.
The novel's central battle sequence is the Battle of Brenna, the war's decisive engagement. Field Marshal Menno Coehoorn leads Nilfgaardian cavalry against the armies of the Northern Kingdoms, commanded by Constable Jan Natalis. The dwarven Volunteer Regiment and the Free Mercenary Company bear the heaviest fighting, while the halfling surgeon Milo "Rusty" Vanderbeck operates continuously in the field hospital. Reinforcements turn the tide, and Coehoorn is killed during his retreat. Jarre, a young temple scribe who volunteered for the army out of love for Ciri, loses his left hand in the fighting.
Ciri arrives at Stygga Castle and surrenders to Vilgefortz, offering herself in exchange for Yennefer's freedom. Vilgefortz rejects the offer, revealing his plan to harvest her placental blood to gain power over all worlds. Geralt's rescue party storms the castle, and the assault exacts devastating losses. Milva is killed by a crossbow bolt after standing exposed to provide covering fire. Cahir dies fighting the bounty hunter Bonhart in single combat to buy Ciri time. Angoulême bleeds to death from a thigh wound. Regis, attacking Vilgefortz in vampire form, is destroyed when the sorcerer melts him with white fire. Geralt uses Fringilla's amulet to deceive Vilgefortz during their final duel, then beheads him. Ciri kills Bonhart in a prolonged sword fight, severing his throat after he treacherously attacks with a hidden knife.
Emperor Emhyr arrives with his elite guard and takes Ciri into custody. He reveals he is Duny, the Enchanted Urcheon who married Ciri's mother Pavetta: He is Ciri's father. Prophecy demands he beget an incestuous child with Ciri to produce a world-saving heir. Geralt condemns the plan. In a pivotal reversal, Emhyr watches Ciri weep, embraces her, and whispers "Farewell, my daughter," ordering all his forces to withdraw.
The Peace of Cintra establishes a new political order, with the Lodge manipulating negotiations from behind the scenes. Emhyr marries the false Ciri, a double raised in his court, making her Empress of Nilfgaard. The Scoia'tael, elven guerrilla fighters who allied with Nilfgaard during the war, see their commanders handed over as war criminals.
Geralt, Ciri, and Yennefer travel together through Ebbing, visiting sites of Ciri's traumatic past. They rescue Dandelion from execution in Toussaint. Geralt declares he is retiring, insisting that protecting Yennefer and Ciri matters more to him than monster-hunting. Ciri then appears before the Lodge at Montecalvo, where she is told to become the lover of Prince Tankred Thyssen of Kovir and bear his child. She demands time and permission to visit Geralt in Rivia first. Fringilla Vigo's vote creates a narrow majority in favor, and Philippa Eilhart, the Lodge's leader, adds her own by invoking destiny. Ciri chooses the surname "of Vengerberg, daughter of Yennefer," asserting her bond with her adoptive mother.
In Rivia, a pogrom erupts against the non-human population. Geralt takes up his sword to defend fleeing dwarves and is mortally wounded by a pitchfork. Yennefer collapses from magical exhaustion trying to heal him. The sorceress Triss Merigold, a longtime ally, overcomes her fear and unleashes a devastating hailstorm that halts the riot. Ciri arrives, and the unicorn Ihuarraquax appears from the fog. Ciri channels the Elder Blood's power through his glowing horn to heal Geralt. Dandelion, Triss, and the dwarves carry Geralt and the unconscious Yennefer into a barge. Ciri tells Triss she cannot stay and pushes the vessel into the mist.
Geralt awakens beneath apple trees with Yennefer beside him. In the frame narrative's conclusion, Ciri tells Galahad, through tears, that Geralt and Yennefer married and lived happily, "like in a fairy tale." She accepts Galahad's invitation to ride toward Camelot, reasoning that in every world there is work for a witcher. They ride together into the setting sun, and before them is everything.