Summary from Goodreads
Magic is dangerous--but love is more dangerous still.
When sixteen-year-old Tessa Gray crosses the ocean to find her brother, her destination is England, the time is the reign of Queen Victoria, and something terrifying is waiting for her in London's Downworld, where vampires, warlocks and other supernatural folk stalk the gaslit streets. Only the Shadowhunters, warriors dedicated to ridding the world of demons, keep order amidst the chaos.
Kidnapped by the mysterious Dark Sisters, members of a secret organization called The Pandemonium Club, Tessa soon learns that she herself is a Downworlder with a rare ability: the power to transform, at will, into another person. What's more, the Magister, the shadowy figure who runs the Club, will stop at nothing to claim Tessa's power for his own.
Friendless and hunted, Tessa takes refuge with the Shadowhunters of the London Institute, who swear to find her brother if she will use her power to help them. She soon finds herself fascinated by--and torn between--two best friends: James, whose fragile beauty hides a deadly secret, and blue-eyed Will, whose caustic wit and volatile moods keep everyone in his life at arm's length...everyone, that is, but Tessa. As their search draws them deep into the heart of an arcane plot that threatens to destroy the Shadowhunters, Tessa realizes that she may need to choose between saving her brother and helping her new friends save the world...and that love may be the most dangerous magic of all.
Oh, I had missed the Nephilhem so! I don't know why I put off reading for so long. I had missed the Shadowhunters and thought that only Clary and Jace could satisfy my hunger, but I was wrong. The sweet Jem, strong Tessa, and the mysterious aloof Will. It is really hard to not give spoilers, but I'll try. Tessa just reminds me of Clary so much, but they are different in their strengths. Jem is sweet and sick and I really don't know much about him. Right now he is more brotherly material, but he has potential. And William Herondale. *sighing head shake* Black hair, blue eyes, sexily arrogant and utterly frustrating, but what more could you expect from an ancestor of Jace's. Pair them all with Tessa's awesome power and evil automatons and you have an unforgettable start of a glorious series. I love the quotes and parts of poems at the beginning of the chapters. I think that books in the past require a lot more research and the time is what made Clockwork Angel so good. Consider yourself warned, if you thought The Mortal Instruments were wonderful, Cassandra Clare will stun you with this one.