Julian Blackthorn confesses to Magnus Bane that his parabatai bond with Emma Carstairs has been changed by their love, asking him to put a spell that dampens his feelings.

During the funeral, Emma meets with her distant cousin, Jem, telling her about Kit Herondale's fey heritage as well as a warlock sickness supposedly caused by ley lines.

Horace states his plans to interrogate all Downworlders and bars Emma and Julian from leaving with the other Blackthorns back to Los Angeles.

Kieran heads to Los Angeles and saves Cristina Rosales and Mark Blackthorn as they are attacked by faeries while investigating a ley line.

Nene offers Emma and Julian the chance to replace her and another sympathetic faerie's positions to accompany the Seelie Queen during her parley with the Unseelie King to regain her son, Ash.

Infiltrating the Unseelie Tower, they confront Annabel and the King, Arawn, revealed to be subjecting Ash to spells from the Black Volume, causing him to attract people to care for him.

In this reality, Clary was killed during the Battle of the Burren, allowing Sebastian Morgenstern, with Jace's and the Endarkened's help, to conquer the world, causing lands to decay in a phenomenon known as Blight, which serves as portals for demons to cross over.

Shadowhunters have lost their angelic power and split between the many siding with Sebastian and calling themselves the Legion of the Star, and those striving for freedom with the Downworlders, known as the Resistance.

Julian has Magnus remove the dampening spell, before calling on a meeting of anti-Registry Shadowhunters and Downworlders to expose the Cohort's lies, under the name "Livia's Watch".

The parley between the Cohort and the Unseelie Court is interrupted by Livia's Watch, who expose Horace's lies by forcing Manuel to divulge the truth using the alternate Mortal Sword, before escalating into open warfare.

It is also revealed that Shade, the warlock who helped Ty find the ingredients for the ritual, is actually Ragnor Fell, Magnus' friend long thought to be dead.

As Julian cradles her, their parabatai bond is strengthened by their love, transforming them into gigantic monsters that kill Horace and swiftly dispose their enemies.

During the Clave meeting, the Cohort refuse to surrender, so Alec Lightwood, having been proclaimed as the new Consul after Jia's abdication, leads the anti-Cohort Shadowhunters to leave Idris and never return.

Common Sense Media said that it was more 'soap opera saga than fantasy tome' due to all of the character-related drama taking away from the main action of the book.

Many other fans have complained that it doesn't have a resolved ending, due to the fact that Cassandra Clare plans on returning to these characters in her upcoming series, The Wicked Powers.