I started this book straight after finishing Clockwork Angel and I just enjoyed it so much more than the last book and am now really interested to know how it ends (even though I kind of already know because of City of Heavenly Fire).
This book definitely focuses less on the plot of the series, defeating Mortmain, and more on the characters, especially Tessa, Jem and Will. I was surprised that I enjoyed all the character development and didn't mind the plot being a kind of a minor thing in this book, and although the love triangle is getting frustrating it's still being done very well and instead of being annoyed by the fact that it's a love triangle, I just feel really bad for Tessa and the situation she's in. I really enjoy Tessa and her narration, which I think is why a lot of people like this series better than the Mortal Instruments series because in that Clary is the narrator for the majority of the story and she can get so frustrating, but Tessa is really logical and she constantly either makes good decisions or has good reasons for her decisions, unlike Clary, and also she's just a really lovely and interesting character who I want to know more about. My favourite characters in this book were Sophie and Henry. Henry continued to be a very gentle character and in this book his love for Charlotte made me like him even more, and even though he must be around Charlotte's age, 23, I always think of him as like a middle aged kind of man because he's such a stabilising father figure to everyone. Sophie really surprised me with how much she was in this book and how important she became, but I really enjoyed learning more about her and I really just like her character and her appearances always make me happy. I would definitely recommend reading this, even if you didn't like the first book in the series because it is so different from it in many ways.
The book starts two weeks after the end of the last book at a Consul meeting where Benedict Lightwood challenges Charlotte for the leadership of the London Institute and the Consul then tells her she has two weeks to either find Mortmain or have strong evidence pointing to where he is or Benedict can run the Institute. Will tells Magnus that when he was twelve he opened a pyxis that his dad had kept from his shadowhunting days and the demon that emerged told him he'd put a curse on him where everyone that loves him would die, starting with his older sister who was helping him fight the demon off. His sister died that night and that's why he left his family and went to the Institute and that's why he's mean to everyone but Jem, who is already dying so he doesn't feel as bad getting close to him. He wants Magnus to find and summon the demon so he can get him to lift the curse so he can be with Tessa. They soon learn that Jessamine is seeing Nate and Sophie knocks her out when she was leaving for a party at the Lightwood's to meet him so Tessa changes into her and goes in her place. Once there she learns that Jessamine had been spying on them and reporting everything to Nate, who was telling the Magister everything, and that Benedict Lightwood was also working for the Magister. Will runs off after the demon who cursed him when he sees him at the party and then Tessa returns to the Institute and tells Charlotte what she learned, Charlotte then questions Jessamine with the mortal sword and then when they see Mortmain has placed blocks in her mind from telling them anything about him, she sends her to the City of Bones with the silent brothers. They get Jessamine to give them one of her and Nate's meeting places and Tessa changes into her again to go meet him but he already knows it's her and has an automaton nearby to take her. Will and Jem fight it off, but Tessa then changes into Nate and orders it to only listen to her and to pick up Nate, then she throws an invention Henry gave them to blow it up on it and Will dives on her and covers her with his body and gets impaled by shards of metal from the explosion. Nate then dies and Tessa faints after realizing she was also hurt in the explosion. Will gets a note from Magnus so he goes to see him and when they summon the demon, they learn that there was no curse on Will, the reason his sister died was because the demon got her with his stinger. The next morning Jem comes into Tessa's room and proposes to her and she accepts. Sophie tells them that she's been seeing Gideon Lightwood and that he knows what Mortmain has over his father, he has demon pox and Mortmain promises a cure. They learn that Lightwood's wife committed suicide because she had caught demon pox from her husband and they use that to blackmail him into giving up his challenge on the institute. Will tells Tessa of the fake curse and goes to kiss her, but she tells him of her engagement to Jem and when he tells her to break it off she realizes she can never do that, Jem thought he would die without love and even if he forgave her, she would ruin the bond between him and Will. The book ends with Will's younger sister Cecily coming to the institute to be trained as a shadowhunter.