“With all due respect,” said Zachariah in his soft voice. “I don’t think you should do that.”

“Why not?” Patrick demanded.

Because you have information now that the Faerie Queen does not know you have, said Brother Enoch. It is rare that that happens. In war there are advantages of power, but also advantages of knowledge. Do not squander this one.

Jia hesitated. “Things may be worse than you know,” she said, and drew something from the pocket of her coat. It was a fire-message, addressed to her from the Spiral Labyrinth. She handed it to Zachariah.

He seemed to freeze in place. For a moment he simply looked at it; then he brushed a finger over the paper, and she realized he was not reading it but rather tracing the signature of the writer of the letter, a signature that had clearly struck him like an arrow to the heart.

Theresa Gray.

“Tessa says,” he said finally, and then cleared his throat, for his voice had emerged ragged and uneven. “She says that the warlocks of the Spiral Labyrinth have examined the body of Amalric Kriegsmesser. That his heart was shriveled, his organs desiccated. She says they are sorry, but there is absolutely nothing that can be done to cure the Endarkened. Necromancy might make their bodies move again, but their souls are gone forever.”

“Only the power of the Infernal Cup keeps them alive,” said Jia, her voice throbbing with sorrow. “They are dead inside.”

“If the Infernal Cup itself could be destroyed . . . ,” Diana mused.

“Then it might kill them all, yes,” said Jia. “But we do not have the Infernal Cup. Sebastian does.”

“To kill them all in one sweep, it seems wrong,” said Tomas, looking horrified. “They are Shadowhunters.”

“They are not,” said Zachariah, in a voice much less gentle than Jia had come to associate with him. She looked at him in surprise. “Sebastian counts on us thinking of them as Shadowhunters. He counts upon our hesitation, our inability to kill monsters that wear human faces.”

“On our mercy,” said Kadir.

“If I were Turned, I would want to be put out of my misery,” said Zachariah. “That is mercy. That is what Edward Longford gave his parabatai, before he turned his sword on himself. That is why I paid my respects to him.” He touched the faded rune at his throat.

“Then do we ask the Spiral Labyrinth to give up?” asked Diana. “To cease searching for a cure?”

“They have already given up. Did you not listen to what Tessa wrote?” said Zachariah. “A cure cannot always be found. At least, not in time. I know—that is, I have learned—that one cannot rely upon it. It cannot be our only hope. We must mourn the Endarkened as dead, and trust in what we are: Shadowhunters, warriors. We must do what we were made to do. Fight.”

“But how do we defend ourselves against Sebastian? It was bad enough when it was just the Endarkened; now we must fight the Fair Folk as well!” Tomas snapped. “And you’re just a boy—”

“I am a hundred and forty-six years old,” said Zachariah. “And this is not my first unwinnable war. I believe we can turn the betrayal of the faeries into an advantage. We will require the help of the Spiral Labyrinth to do it, but if you will listen to me, I will tell you how.”

Clary, Simon, Jace, Alec, and Isabelle picked their way in silence through the eerie ruins of Alicante. For Jace had been right: It was Alicante, unmistakably so. They had passed too much that was familiar for it to be anything else. The walls around the city, now crumbled; the gates, corroded with the scars of acid rain. Cistern Square. The empty canals, filled with spongy black moss.

The hill was blasted, a bare heap of rock. The marks where there had once been pathways were clearly visible like scars along the side. Clary knew that the Gard should be at the top of it, but if it still stood, it was invisible, hidden in gray fog.

At last they clambered over a high mound of rubble and found themselves in Angel Square. Clary took a breath of surprise—though most of the buildings that had ringed it had fallen, the square was surprisingly unharmed, cobblestones stretching away in the yellowish light. The Hall of Accords was still standing.

It wasn’t white stone, though. In the human dimension, it looked like a Greek temple, but in this world it was lacquered metal. A tall square building, if something that looked like molten gold that had been poured out of the sky could be described as a building. Massive engravings ran around the structure, like ribbon wrapping a box; the whole thing glowed dully in the orange light.

“The Accords Hall.” Isabelle stood with her whip coiled around her wrist, looking up at it. “Unbelievable.”

They started up the steps, which were gold streaked with the black of ash and corrosion. At the top of the stairs, they paused to stare at the huge double doors. They were covered with squares of hammered metal. Each one was an engraved panel showing an image. “It’s a story,” Jace said, stepping closer and touching the engravings with a black-gloved finger. Writing in an unfamiliar language scrolled along the bottom of each illustration. He glanced over at Alec. “Can you read it?”

“Am I the only person who paid attention in language lessons?” Alec demanded wearily, but he stepped up to look more closely at the scrawl. “Well, first, the panels,” he said. “They’re a history.” He pointed at the first one, which showed a group of people, barefoot and in robes, cowering as the clouds above them opened up and a clawed hand reached down toward them. “Humans lived here, or something like humans,” Alec said, pointing at the figures. “They lived in peace, and then demons came. And then—” He broke off, his hand on a panel whose image was as familiar to Clary as the back of her own hand. The Angel Raziel, rising out of Lake Lyn, the Mortal Instruments in hand. “By the Angel.”

“Literally,” said Isabelle. “How—Is that our Angel? Our lake?”

“I don’t know. This says the demons came, and the Shadowhunters were created to battle them,” Alec went on, moving along the wall as the panels progressed. He jabbed his finger at the scrawl. “This word, here, it means ‘Nephilim.’ But the Shadowhunters rejected the help of Downworlders. The warlocks and the Fair Folk joined with their infernal parents. They sided with the demons. The Nephilim were defeated, and slaughtered. In their last days they created a weapon that was meant to hold the demons off.” He indicated a panel showing a woman holding up a sort of iron rod with a burning stone set into the end of it. “They didn’t have seraph blades; they hadn’t developed them. It doesn’t look like they had Iron Sisters or Silent Brothers, either. They had blacksmiths, and they developed some sort of weapon, something they thought might help them. The word here is ‘skeptron,’ but it doesn’t mean anything to me. Anyway, the skeptron wasn’t enough.” He moved to the next panel, which showed destruction: the Nephilim lying dead, the woman with the iron rod crumpled on the ground, the rod itself cast aside. “The demons—they’re called asmodei here—burned away the sun and filled the sky with ash and clouds. They ripped fire from the earth and razed the cities to the ground. They killed everything that moved and breathed air. They drained the seas until everything in the water was dead too.”