Suddenly Dru shrieked. Another figure raced up the street. A second faerie knight, this one a woman with armor of pale green, carrying a shield of overlapping carved leaves.

Emma whipped a knife from her belt and threw it. Instinctively the faerie raised her shield to block the knife—which sailed past her head, and severed the cord holding a pair of scissors to the roof above. The scissors fell, blade-first, and plunged between the faerie woman’s shoulders. She fell to the ground with a shriek, her body spasming.

“Good job, Emma,” said Helen in a hard voice. “Come on, all of you—”

She broke off with a cry as three Endarkened surged from a side street. They wore the red gear that had appeared so often in Emma’s nightmares, dyed even redder by the light from the demon towers.

The children were as silent as ghosts. Helen raised her crossbow and shot a bolt. It struck one of the Endarkened in the shoulder, and he spun away, staggering but not falling. She fumbled to reload the bow; Julian struggled to hold Tavvy while reaching for the blade at his side. Emma put her hand on Cortana—

A spinning circle of light hurtled through the air and buried itself in the throat of the first Endarkened, blood spattering the wall behind him. He clawed at his throat, once, and fell. Two more circles flew, one after the other, and sliced into the chests of the other Dark Nephilim. They crumpled silently, more blood spreading in a pool along the cobblestones.

Emma whirled and looked up. Someone stood at the top of the stairs: a young Shadowhunter with dark hair, a gleaming chakhram still in his right hand. Several others were hooked to his weapons belt. In the red light of the demon towers he seemed to glow—a tall, thin figure in dark gear against the darker black of night, the Accords Hall rising like a pale moon behind him.

“Brother Zachariah?” said Helen in amazement.

“What’s going on?” Magnus asked hoarsely. He was no longer able to sit up, and was lying, half-propped on his elbows, on the floor of the cell. Luke was standing with his face pressed to the arrow-slit window. His shoulders were tense, and he’d barely moved since the first screams and shouting had begun.

“Light,” Luke said, finally. “There’s some kind of light pouring out of the keep—it’s burning the mist away. I can see the plateau down below, and some of the Endarkened running around. I just don’t know what’s caused it.”

Magnus laughed under his breath, and tasted metal in his mouth. “Come on,” he said. “Who do you think?”

Luke looked at him. “The Clave?”

“The Clave?” Magnus said. “I hate to break it to you, but they don’t care enough about us to come here.” He tipped his head back. He felt worse than he could remember ever feeling—well, maybe not ever. There had been that incident with the rats and the quicksand around the turn of the century. “Your daughter, though,” he said. “She does.”

Luke looked horrified. “Clary. No. She shouldn’t be here.”

“Isn’t she always where she isn’t supposed to be?” Magnus said in a reasonable voice. At least, he thought he sounded reasonable. It was hard to tell when he felt so dizzy. “And the rest of them. Her constant companions. My . . .”

The door burst open. Magnus tried to sit up, couldn’t, and fell back onto his elbows. He felt a dull sense of annoyance. If Sebastian had come to kill them, he’d rather die on his feet than his elbows. He heard voices: Luke, exclaiming, and then others, and then a face swam into view, hovering over his, eyes like stars in a pale sky.

Magnus exhaled—for a moment he no longer felt ill, or afraid of dying, or even angry or bitter. Relief washed over him, as profound as sorrow, and he reached up to brush the cheek of the boy leaning over him with the back of his bruised knuckles. Alec’s eyes were huge and blue and full of anguish.

“Oh, my Alec,” he said. “You’ve been so sad. I didn’t know.”

As they forged their way farther into the center of the city, the crowd thickened: more Nephilim, more Endarkened, more faerie warriors—though the faeries moved sluggishly, painfully, many of them weakened by contact with the iron, steel, rowan wood, and salt that had been liberally deployed around the city as protection against them. The might of faerie soldiers was legendary, but Emma saw many of them—who might otherwise have been victorious—fall beneath the flashing swords of the Nephilim, their blood running across the white flagstones of Angel Square.

The Endarkened, however, were not weakened. They seemed unconcerned with the troubles of their faerie companions, hacking and slashing their way through the Nephilim jamming Angel Square. Julian had Tavvy zipped into his jacket; the little boy was screaming now, his cries lost among the shrieks of battle. “We have to stop!” Julian shouted. “We’re going to be separated! Helen!”

Helen was pale and ill-looking. The closer they got to the Hall of Accords, now looming above them, the thicker the clusters of faerie protection spells were; even Helen, with her partial heritage, was beginning to feel it. It was Brother Zachariah—just Zachariah now, Emma reminded herself, just a Shadowhunter like they were—in the end who moved to fashion them all into a line, Blackthorns and Carstairs, everyone hand in hand. Emma hung on to Julian’s belt since his other hand was supporting Tavvy. Even Ty was forced to hold hands with Drusilla, though he scowled at her when he did it, bringing fresh tears to her eyes.

They made their way toward the Hall, clinging together, Zachariah in front of them; he was out of throwing blades and had taken out a long-bladed spear. He swept the crowd with it as they went, efficiently and icily hacking a pathway through the Endarkened.

Emma burned to seize Cortana out of its scabbard, to run forward and stab and slash at the enemies who had murdered her parents, who had tortured and Turned Julian’s father, who had taken Mark away from them. But that would have meant letting go of Julian and Livvy, and that she would not do. She owed the Blackthorns too much, Jules especially, Jules who had kept her alive, who had brought her Cortana when she had thought she would die of grief.

Finally they stumbled up the front steps of the Hall behind Helen and Zachariah, and reached the massive double doors of the entryway. There was a guard on either side, one holding an enormous wooden bar. Emma recognized one of them as the woman with the koi tattoo who sometimes spoke out in meetings: Diana Wrayburn. “We’re about to shut the doors,” said the one holding the bar. “You two, you’re going to have to leave them here; only children are allowed inside—”

“Helen,” said Dru in a trembling little voice. The line broke into pieces then, with the Blackthorn children swarming Helen; Julian standing a little aside, his face blank and ashen, his free hand stroking Tavvy’s curls.

“It’s all right,” Helen was saying in a choked voice. “This is the safest place in Alicante. Look, there’s salt and grave dirt all up and down the steps to keep the faeries out.”

“And cold iron under the flagstones,” said Diana. “The instructions of the Spiral Labyrinth were followed to the letter.”

At the mention of the Spiral Labyrinth, Zachariah took in a sharp breath and knelt down, bringing his eyes on a level with Emma’s. “Emma Cordelia Carstairs,” he said. He looked both very young and very old at the same time. There was blood at his throat where his faded rune stood out, but it wasn’t his. He seemed to be searching her face, though for what, she couldn’t tell. “Stay with your parabatai,” he said finally, so quietly that no one else could hear them. “Sometimes it’s braver not to fight. Protect them, and save your vengeance for another day.”