Love and lies can corrupt even the purest heart... In the magical underworld of Victorian London, Tessa Gray finds her heart drawn more and more to Jem, while her desire for Will, despite his dark moods, continues to unsettle her. But something is changing in Will - the wall he has built around himself is crumbling. Could finding the Magister free Will from his secrets and give Tessa the answers about who she is and what she was born to do? As their dangerous search for the truth leads the three friends into peril, Tessa's heart is ever more torn, especially when one of their own betrays them...

Cassandra Clare is the author of the internationally bestselling Mortal Instruments, The Infernal Devices, The Bane Chronicles, The Shadowhunter's Codex and Tales from the Shadowhunter Academy. There are more than 40 million copies of her books in print worldwide. They have been translated into over 30 languages and have appeared globally on bestseller lists. The Mortal Instruments: City of Bones is now a major movie. Cassandra lives in Massachusetts, USA. She is currently working on two new Shadowhunter series, The Dark Artifices and The Last Hours. Visit her online at CassandraClare.com. Learn more about the world of the Shadowhunters at UKShadowhunters.com.