Throne of Glass is the first novel in the eight-book young adult (YA) fantasy series of the same name by author Sarah J. Maas. First published in 2012, the novel is loosely based on the Cinderella story. Throne of Glass was critically well-received. In 2016, Disney purchased the rights to a television adaptation. In addition to the Throne of Glass series, Sarah J. Maas is the author of a second High Fantasy series, A Court of Thorns and Roses, intended for adult readers.

Plot Summary

After a year enslaved in the Endovier Salt Mines, teenage assassin Celaena Sardothien is brought before Dorian Havilliard, the Crown Prince of the country of Adarlan. The King of Adarlan is holding a tournament to determine his Champion--really a personal assassin on retainer—and members of the court have been invited to sponsor competitors. Dorian proposes to sponsor Celaena, notorious for assassinating many members of the King’s court before her imprisonment, in order to annoy his father. In return, Celaena will be free after four years of service. Celaena agrees and journeys to the glass castle at Rifthold, Adarlan’s capital, to compete.

Celaena despises the royal family because the tyrannical King of Adarlan murdered her family. Celaena is living undercover: She is actually Aelin Galathynius, the lost princess of the conquered kingdom of Terrasen, though this is never explicitly revealed in Throne of Glass.

At Rifthold, Celaena discovers an ominous clock tower surrounded by mysterious runes. Chaol Westfall, the young Captain of the Adarlan Guard struggles to trust Celaena, believing her to be a danger to Dorian, but as Dorian becomes infatuated with Celaena, Celaena and Chaol form a tentative friendship as he trains her for the competition. Celaena meets two young women: the vain and ambitious Kaltain Rompier who schemes to marry Dorian, and the princess Nehemia Ytger, a spy on behalf of her home kingdom of Eyllwe, which is at war with Adarlan.

The tournament for Champion consists of a series of Tests followed by a final duel. The cruel and enormous Cain emerges as Celaena’s primary competitor after he narrowly defeats her in the first Test, which Celaena loses on purpose to hide her true skills. During the competition, competitors are found murdered and horribly mutilated, their corpses surrounded by runes written in blood. Chaol struggles to solve the murders, and Celaena fears for her safety.

One night, Celaena discovers a secret tunnel that leads to the tomb of Elena Galathynius Havilliard, first Queen of Adarlan and first Princess of Terrasen—Celaena’s distant ancestor. Celaena learns that she must find and defeat a mysterious evil that threatens the world. Later in the secret passageway, Celaena finds Cain using runes to summon a ridderak, a demonic creature to whom Cain is sacrificing the other competitors to steal their strength. Cain flees, and Celaena slays the ridderak with a sword from Elena’s tomb.

At the Yulemas masquerade, Celaena and Dorian dance and share a passionate kiss. Chaol also realizes he has feelings for Celaena.

At the final duel, Cain, supernaturally altered, torments Celaena physically and mentally, nearly killing her. Celaena’s hallucinations reveal demons summoned by Cain. Nehemia magically summons Elena, who interferes, allowing Celaena to defeat Cain and win the tournament.

After the duel, Celaena tells Dorian their relationship is impossible, as she is now the King’s Champion. Dorian forces his father to abandon a plan to make Nehemia a prisoner of war, standing up to the King for the first time. Elena appears to Celaena again, telling her that her destiny is yet unfulfilled, and that Celaena will save many people. As Celaena signs the contract to be Champion, she wonders how she will undermine the King while she serves him, looking forward to her eventual freedom.