In City of Heavenly Fire, Clary, Jace and co. are on a mission to stop Clary’s evil brother, Sebastian, from destroying the Shadowhunters (Nephilim) who protect the Earth against demons. After a flurry of attacks, New York is deemed no longer safe, and the Shadowhunters retreat to their home country of Idris.
It seems that the only way to stop Sebastian is to use the heavenly fire that is coursing through Jace’s veins, but Jace is struggling to control the fire within him, let alone weaponise it. Sebastian remains fixated on Clary, but it could be Jace who truly understands the madness within his quasi-brother.
The final installment in The Mortal Instruments series builds on Cassandra Clare’s other Shadowhunter novels in a way that will be entirely satisfying to fans and confusing to all others.
There is the sense when reading City of Heavenly Fire that Clare is checking things off a long list. Romantic entanglements? Check. Mentions of incest? Check. Action scenes ending with long speeches? Check, check, check. It isn’t a bad thing — after all, readers of Heavenly Fire will be fans of The Mortal Instruments (or, at least invested enough to want to know how it ends); they will be used to these conventions, and they will like them. After five previous installments, the style and the structure of this story is familiar, like an old friend.
In fitting with these conventions, the final installment of The Mortal Instruments is not short on plot. This vacillates between action and romance; the characters might be battling against the evil Jonathan Morgenstern, but they still find time to worry about their own romantic troubles.
This is a familiar pattern for Mortal Instruments fans, as is the high body count. City of Heavenly Fire opens with a double murder, and the first main character loses their life in the first 150 pages. By the time the novel closes, they are not the only one. Emotional upheaval caused by the death of beloved characters? Check.
That is not to say that Heavenly Fire is not a good book. Clare’s writing is punchy, and she knows her world inside out. The characters speak with believable voices, and the dialogue is enough to make you laugh out loud more than once. The plot rattles on at a page-turning pace, and even though you know to expect twists, the revelations themselves are a surprise.
If there is to be a criticism of City of Heavenly Fire, it is this: the book is too reliant on Clare’s other Shadowhunter works. If readers are not familiar with prequel series The Infernal Devices, or the companion novellas that comprise The Bane Chronicles, they will be left in the dark at many points during the story.
Similarly, too much time is spent introducing the characters that will feature in The Mortal Instruments followup The Dark Artifices. For those who do not plan to read the companion series, these sections offer very little to the narrative and cause the pace to idle frustratingly.
Despite all of this, if this was a checklist, Heavenly Fire would tick every box that a Mortal Instruments fan could want. If you are a fan of Shadowhunters and Downworlders, and can keep your Herondales straight from your Blackthorns, you will find a satisfying conclusion to The Mortal Instruments series in City of Heavenly Fire.