2 months after CoLS Clary finds herself taken by her brother and someone she thought long dead. Jace has no clue she's been taken and she is pushed to the breaking point with Sebastian, his new rune and his intentions. Along with the intentions of the dead acquaintance, she struggles to survive and retain her sanity as she is used for the purposes of evil to bring down the Clave.

“You’re mine Clary, don’t you get it by now?" Sebastian yelled, his rage boiling over like an erupting volcano. "Screw Jace – not like you need encouragement – just give in and accept that we’re meant for each other! Forget about Jace!” Clary screamed as she felt her rune activate, and memories in the back of her mind were burned away. Memories of a boy with bright golden eyes.

Everyone Clary loves is gone and she's on her own. Except for her brother, who she realizes only wants the best for his little sister and comes to take her away. After going with him she battles her own inner demons while Jonathan pushes her towards war. Jonathan is the only thing Clary has left but can she live with her own choices?