Clockwork Angel:
Love is the most dangerous magic of all... First in the bestselling prequel series to The Mortal Instruments, set in Victorian London. Something terrifying is waiting for Tessa Gray in London’s Downworld, where vampires, warlocks and other supernatural folk stalk the gaslit streets.

Clockwork Prince:
Love and lies can can corrupt even the purest heart… Second in the bestselling prequel series to The Mortal Instruments, set in Victorian London. Tessa Gray find her heart drawn more and more to Jem, while her longing for Will, despite his dark moods, continues to unsettle her.
 
Clockwork Princess:
Danger and betrayal… Secrets and enchantment… Third and final book in the bestselling prequel series to The Mortal Instruments, set in Victorian London. A net of shadows begins to tighten around the Shadowhunters of the London Institute.