A Court of Mist and Fury

The endgame begins when Feyre, Rhysand, and the Inner Circle attempt a covert mission into Hybern to destroy the Cauldron before the King can use it to shatter the Wall between the human and Fae lands. The plan collapses: Feyre never gets the chance to speak the nullifying spell, and the entire group is captured. Their captor is Jurian, resurrected and bound to the King of Hybern's will, who uses an ash bolt to hold Azriel's life hostage while magic-suppressing bonds are placed on the rest of the group.

The captivity reveals the full scope of the betrayal. Tamlin, believing he is rescuing Feyre from Rhysand, has allied with the King of Hybern and brought Lucien along; neither of them knew that Feyre's human sisters, Nesta and Elain, would also be seized. Ianthe is exposed as the one who gave up the sisters' location, driven by her ambition to see the High Lords replaced by rule of the High Priestesses. To prove the Cauldron's power to the assembled mortal queens, the King forces it to transform both Nesta and Elain into High Fae against their will. In the middle of this horror, Lucien declares that Elain is his mate.

Unseen by her captors, Feyre has secretly been working her own magic loose from the binding spells the entire time. Once she's sure her friends can get free, she plays along, pretending memory loss and affection for Tamlin, and begs the King to sever her bond to Rhysand. He grants it — but he only breaks the bargain requiring her monthly visits; the true mating bond and their mental connection remain intact, unknown to him. Under this cover, her friends escape back to the Night Court with the Book of Breathings and with Feyre's transformed sisters in tow, while Rhysand begins preparing the Night Court for the coming war with Hybern.

Feyre herself goes with Tamlin back to the Spring Court, playing the part of the grateful, rescued fiancée so she can act as an inside asset. But what neither Tamlin nor anyone in Hybern knows is that only the night before, Rhysand named Feyre High Lady of the Night Court — an unprecedented title — leaving her poised to reenter the story not as a captive or a bride, but as a ruler in her own right when the war finally comes.

Feyre Archeron ended book one physically remade into High Fae but psychologically shattered by what she endured and did Under the Mountain. This book opens on her unraveling engagement to Tamlin, High Lord of the Spring Court, who tries to keep her safe by keeping her confined, refuses to let her train her new powers, and denies her any real say in her future. When her wedding-day panic peaks, Rhysand, High Lord of the Night Court, arrives to collect on the bargain she made with him and pulls her into his world instead.

At the Night Court, Feyre discovers Rhysand is far more complex than his monstrous reputation, and meets his Inner Circle: Morrigan, the warrior cousins Cassian and Azriel, and the ancient, feral Amren. She learns Rhysand endured being Amarantha's captive specifically to protect his hidden, untouched city of Velaris, and that he has known for a long time that he and Feyre are true mates — something confirmed to her later by the all-knowing Suriel. After a period of anger at his secrecy, Feyre and Rhysand complete the mating bond.

Meanwhile the larger threat solidifies: the King of Hybern is assembling the pieces to reactivate the Cauldron — a device that can shatter the Wall separating the mortal and Fae realms — including the two halves of the Book of Breathings, one held by the mortal queens and one by the Summer Court's High Lord Tarquin. Feyre trains extensively in combat and in her patchwork High Lord-derived powers (including reading minds as a daemati). The Inner Circle steals one half of the Book from Tarquin's territory and eventually persuades one of the mortal queens to covertly hand over the other half, after showing the queens Velaris to prove Rhysand isn't the monster of rumor.

During the story, deep rifts open with the Spring Court: Feyre learns Tamlin's family and Rhysand's family have a blood history of mutual slaughter, and Tamlin's controlling behavior pushes her fully away from him. A Hybern-orchestrated attempt to infiltrate and destroy the Cauldron ends in disaster — the whole group is captured, and it's revealed that Tamlin, believing he was saving Feyre, has allied with Hybern, aided (unknowingly, as far as the sisters were concerned) by Ianthe's betrayal, which led to Feyre's sisters Nesta and Elain being captured and forcibly turned into High Fae via the Cauldron. Lucien reveals Elain is his mate. Feyre secretly undermines her captors' binding magic and orchestrates an escape for her friends and sisters, letting the King believe he has severed her bond to Rhysand (he has only broken the bargain terms, not the true mating bond).

The book ends with Feyre returning to the Spring Court alongside Tamlin as an undercover operative, while Rhysand and the Night Court prepare for outright war against Hybern. Unknown to Tamlin or Hybern, Rhysand named Feyre High Lady of the Night Court the night before. Open threads heading into book three: the coming war with Hybern and the King's quest to break the Wall using the Cauldron and the now-reunited Book of Breathings; Feyre's undercover position inside the Spring Court and the danger of her double life; Nesta and Elain's unwanted transformations and their adjustment to Fae life and to the war; Lucien's mating bond with Elain; and Feyre's new, still-unrevealed status as High Lady.