City of Heavenly Fire

by Cassandra Clare

Shadowhunters of the Los Angeles Institute meet to discuss the army of Endarkened Shadowhunters when the army, led by Sebastian Morgenstern, ambush the Institute, endarken some shadowhunters, and kidnap Mark Blackthorn, leaving Mark's five half-siblings and Emma Carstairs to escape to Alicante.

Maryse Lightwood announces to the New York Institute that an emergency meeting is due in Alicante to discuss the attack on five Institutes around the world. Clary Fray reluctantly leaves Simon Lewis to be guarded by Maia Roberts and Jordan Kyle for his safety. However, Simon is kidnapped by Maureen Brown and her vampire aides to be her groom, but Raphael Santiago frees and helps him to come to Alicante. Praetor Lupus, the brotherhood of werewolves, is soon attacked by the Endarkened with Jordan and Praetor Scott among the casualties, resulting in Bat Velasquez and Rufus Hastings battling for the position of pack leader. Rufus is about to deliver the death blow to Bat when Maia Roberts steps in and challenges Rufus. The vacuum of power is finally ended when Maia kills Rufus, becoming the new leader, and also tricks Maureen into drinking holy water so the latter's aide, Lily, can usurp her to become the leader of the vampire clan.

At Alicante, Emma and Julian Blackthorn are interrogated using the Mortal Sword, Clary comforting the former when she breaks into tears. Choosing to accept her Morgenstern heritage, Clary claims Heosphoros, the twin of Sebastian's Phaesphoros, as her sword. The Seelie Queen, now allied with Sebastian, sends Meliorn to ask the Downworlder Representatives (Jocelyn Fray, Luke Garroway, Magnus Bane, and Raphael) to join them; when they refuse, he brings them to Edom, the realm of demons. Jace Herondale is injured during the ensuing conflict and burns Brother Zachariah back into his Shadowhunter persona. An Endarkened soon gives an ultimatum for the Clave to hand over Clary and Jace. Clary, Jace, Simon, and Isabelle and Alec Lightwood, force the Seelie Queen to send them to Edom. Confronting Sebastian, Clary pretends to agree to rule by his side, but then stabs him with Heosphoros, reverting him back momentarily to the brother she could have, Jonathan Morgenstern, who destroys the Infernal Cup before he dies, killing the Endarkened, including Luke's sister, Amatis. To escape Edom, Magnus summons his father, Asmodeus, who offers a way out in exchange for Magnus' immortality and life. Simon offers a lighter option: his immortality and memories of the Shadow World. The Clave punishes the faeries and sends Emma to live with the Blackthorns. Alec and Magnus reconcile and get back together. Meanwhile, Clary scatters Jonathan's ashes in Lake Lyn and mourns for Simon.

Several months later, Jocelyn and Luke hold their wedding, attended by numerous Shadowhunters and Downworlders alike. Simon has remembered bits of the Shadow World as well as his relationship with Isabelle. Attending the wedding is also Tessa Gray and Brother Zachariah (whose identity is not revealed), both of them having formally introduced themselves to Clary.