Clockwork Princess by Cassandra Clare

Tessa has made her choice: she is marrying Jem despite Will's profession of love for her, but Jem is dying. He has used up his store of yin fen, the demon drug that he depends on to live, and the Magister has hoarded the rest in an attempt to get Tessa to cooperate with his evil plan. The Shadowhunters of the London Institute have lost the support of the others who view their leader, Charlotte, as weak and incapable of making sound decisions because she is a woman. So when the Magister sends an army of automatons to bring Tessa to him, it is a simple task. And when they refuse to send anyone after her, Will takes off on his own to bring her home.

This was a very satisfying ending to the trilogy. I will admit (and warn you) DO NOT LOOK INSIDE THE JACKET COVER! I saw something that I thought was a map but turned out to be a family tree. Imagine how disappointed I was when I found out who ends up together before even reading the first page... Aside from that, the story was very well-written in typical Clare-fashion, though I did feel like it was slightly more predictable than her other stories. And I have to admit that I was really excited to find that a theory I had concerning a character from the Mortal Instruments books turned out to be (almost) right!