Jonathan washes up on shore, still alive. He uses his blood and dying breath to open a gateway to Edom on the beach. A demon flies out of the ground and flies toward the city.
Simon and Luke go to Magnus to help with finding Maia. The Seelie Queen organizes a dinner to interrogate Maia with questions about Simon. Maia tries to escape but she's captured.
Clary, Isabelle, Alec and Jace rush downtown to fight the demon flying over the city. Alec shoots it with his arrow; the demon breaks apart. However, the creative separates into smaller demons and escapes.
The Downworlders confront the Seelie Queen about her shady ways. The Queen made a deal with Valentine to bring down the wards and allow him into Idris.
Alec goes to Magnus asking for helping in sealing the rift. He agrees to do so to help save lives.
Clary and Jace go to Idris to warn the Shadowhunter troops. It is in fact a trap; Malakai, the leader of the army/Clave, is a member of the Circle. They're being help prisoner.
Magnus starts to close the portal to Edom as another of the demons emerges from the rift. The group stops the demon in time to seal the portal.
Luke and Simon find Maia in the Seelie forest. The Seelie Queen grants them freedom and demands them to leave the realm.
Malakai plans to execute Clary. Before he's able to do so, Jace invokes his powers and breaks free. He saves Clary in time, but Valentine arrives to stab Jace. With Jace's dying breath, he admits that he loves Clary.
Valentine places the Mortal Cup and the Mortal Sword in Lake Lynn (the Mortal Mirror). He calls on Razeal to appear and wishes all the demons, Downworlders and tratorous Shadowhunters to be killed. Razeal and heaven does not want this, but will allow if he completes the ritual.
Clary breaks free from her chains and fights Valentine. She successfully stops him by stabbing him multiple times. Valentine is dead.
Clary gives her blood and asks of Razeal to bring Jace back from the dead. The wish is granted and Jace is alive again. His parabathai rune with Alec has returned.
The Downworlders and Shadowhunters celebrate over their recent success. Clary and Simon become best friends again, Simon and Maia are on great terms, and Isabelle is happy being "sisters" with Clary.
Magnus and Alec reconcile.
Holly arrives to the party and confronts Luke about him being a werewolf.
Simon returns to the Seelie realm and fulfills his obligation. He had secretly made a deal with the Seelie Queen.
Jace collapses from pain to his chest.
The wraith demons combine together in a mysterious cave to become a woman covered in black. She stands over Jonathan's dead body and calls him "son".