Another book has been relased and reached my home where I have spent a few days reading til late night :D I am quite happy with the result!
The story begins two weeks after City of Fallen Angels, with Jace and Sebastian still missing. Clary, who wants to find Jace, asks the Queen of the Fair Folk to help her using a bell given to her in the previous book.
The queen agrees to help if Clary returns two Faerie rings (which have the power to speak to each other though their minds) that were stolen and kept in the Institute library. Clary agrees, out of desperation to find Jace.
While Clary is in the library looking for the rings, Sebastian and Jace enter, talking like old friends. Shocked, Clary stays hidden while they take some books and leave. That night at Luke’s home, she wakes up to find Jace next to her. Jace tells Clary that he and Sebastian have returned to ask her to join them. They are interrupted when Jocelyn sees Sebastian and screams. A fight breaks loose, in which Luke is stabbed by Sebastian then Jace and Sebastian disappear but before they go, Jace mouths to Clary that he will be back for her.
Clary and Jocelyn move into Magnus’s house for their own safety. Shortly after they arrive Clary and her mom get in to an argument, Clary storms off and then portals out to meet Simon at the diner.
Clary then agrees to join Jace and Sebastian with a view to spying on them, whilst using the Faerie rings to communicate with Simon. Over time, Clary realizes that Jace is possessed and is acting much like Sebastian.
Meanwhile, everyone else is trying to think of a way to kill Sebastian without killing Jace; they are tied together with Lilith’s magic, meaning one cannot be killed without killing the other. Isabelle and Jocelyn go to the Iron Sisters for help and learn that the connection between Sebastian and Jace can be broken using a blade of Heaven, which can only be given by an angel. They come to a solution when Simon suggests summoning Raziel. They agree that Simon should do this because he has the Mark of Cain, making him invincible.
Clary learns from Sebastian that he intends to make a second Mortal Cup with the power to kill all greater demons. Later, Jace manages to revert to his true, non-possessed self for a few minutes to explain Sebastian’s plan to Clary. Jace tells her that Sebastian wants to use Lilith’s blood to create an army of dark Shadowhunters using the second Mortal Cup. Simon and the others travel to Luke’s farmhouse to summon Raziel. There, Raziel gives Simon a blade of Heaven named Glorious, but in return demands the right to strip Simon of the Mark of Cain. Simon agrees and Raziel takes the Mark away, rendering Simon no longer invincible.
Clary and Sebastian travel to “The Seventh Sacred Site” to create an army of new Shadowhunters. Sebastian summons Lilith and mixes her blood in the second Mortal Cup, then demonstrates his creation to his followers by forcing Amatis to drink from the Cup. Simon, Magnus, Alec, Isabelle and Shadowhunters from the Clave then arrive and Sebastian’s dark Shadowhunters meet them in battle. Simon gives the Angel blade to Clary, who tries to hunt down Sebastian. Clary uses the Angel blade and stabs Jace, believing that it won’t kill him as his heart is more good than evil. Jace is set alight, leading the other to believe that he is dead. The battle ends when most of Sebastian’s dark Shadowhunters have been killed, and Sebastian flees.
Clary sees that Jace is not dead and his family take him back to the Institute. After some days, Clary speaks with Jace and learns that after being stabbed by the Angel blade, he now has sacred fire inside him. The sacred fire prevents people from touching him, as doing so will result in them being burned. Magnus breaks up with Alec because he (Alec) considered a way to make Magnus mortal but never told Magnus that Camille made such the offer, even though Alec refused the offer. The story ends with Maryse showing two of the Silent Brothers – Enoch and Zachariah – a pair of angel wings and a note from Sebastian with the words “Erchomai, I am coming”, which she found on the floor of the institute library.