The Infernal Devices

About The Infernal Devices

In Victorian London, orphaned American Tessa Gray arrives to find her brother missing and discovers she has a terrifying power of her own: she can transform into a perfect physical and psychic copy of anyone whose object she holds. Taken in by the Shadowhunters of the London Institute, Tessa is pulled into a fight against the Magister, a mysterious figure building an army of clockwork automatons, while getting caught between two Shadowhunters who could not be more different -- the sardonic, self-destructive Will Herondale and the steady, bookish Jem Carstairs.

A prequel trilogy set roughly 130 years before The Mortal Instruments, The Infernal Devices trades contemporary New York for gaslamp-and-steampunk London, giving Cassandra Clare's Shadowhunter mythology real historical texture -- clockwork monsters, Victorian social constraints, and ancestors of Mortal Instruments characters appearing generations before their descendants. It's frequently cited by fans as the emotional high point of the whole Shadowhunter Chronicles, built on a genuinely difficult love triangle and one of the series' most devastating endings.

Three novels tell one complete, continuous story from Tessa's arrival in London through the trilogy's climactic confrontation with the Magister.

How to read this series

Read the three novels in publication order: Clockwork Angel, Clockwork Prince, Clockwork Princess. It's a complete, continuous trilogy with no gaps to fill in.

Chronologically, The Infernal Devices takes place well before The Mortal Instruments, and many readers recommend reading it either first (for chronological order) or immediately after Mortal Instruments (for publication-adjacent order, since it deepens references and ancestry connections that Mortal Instruments sets up). Either approach works; what matters more is reading The Last Hours after this trilogy, since Last Hours is a direct sequel featuring Infernal Devices characters' children.