“Because of Cristina,” said Kieran. “She would not have agreed to a dishonorable plan. I understand you were trying to help your family, your sister. I understand why you were desperate. And I believe you would not have deceived me longer than you needed.” Something behind his eyes suddenly seemed very old. “I will testify,” he said.

Mark started up. “Kieran, you don’t—”

Kieran’s hands came up to cup Mark’s face. His touch was gentle. “I am not doing it for you,” he said. “This will be what I do for Emma and the others. Then that debt will be paid. You and I, our debts are paid already.” He leaned forward and brushed his lips against Mark’s. Mark wanted to chase the kiss, the warmth of it, the familiarity. He felt Kieran’s hand come down to splay itself over his chest—over the elf-bolt that hung there, below his collarbone. “We will be done with each other.”

“No,” Mark whispered.

But Kieran was on his feet, the warmth of his hands gone from Mark’s skin. His eyes were dark, his whole body tense. Mark shot to his feet after, meaning to demand that Kieran explain what he had meant by done—just as a terrible noise split the air.

It was a noise that came from outside the Institute, though not very far at all. Not nearly far enough. A memory flashed through Mark’s mind, of watching from horseback as a forest of trees was destroyed by lightning. Fire had flashed beneath him, the wrenching crash of branches and trunks like shrieks in his head.

Kieran sucked in a breath. His eyes had gone distant, unfocused. “They have come,” he said. “They are near.”

*

A crash ripped Emma out of sleep and out of Julian’s arms. A crash that wasn’t quite a crash; she thought at first that it sounded like two cars slamming into each other on the highway, the screech of brakes and the explosion of glass. It seemed to be coming from right outside; she bolted up and hurtled across the room to the window.

There were five of them in the courtyard. They gleamed bronze in the morning light, both horses and riders. The steeds seemed metallic, their eyes bound with bronze silk, their hooves gleaming with a high polish. The faeries who sat astride them were just as shimmering and beautiful, their armor without visible jointure so that it looked like liquid bronze. Their faces were masked, their hair long and metallic. Somehow, here in the heart of London, they looked far more terrifying than they had the first time Emma had seen them.

Julian was awake, sitting on the edge of the bed, reaching for the weapons belt that hung on the wall over the nightstand.

“They came,” she said. “It’s the Riders.”

*

They raced to the library, all of them but Kit and Bridget, as Magnus had instructed. Magnus, Cristina, Ty, and Livvy were already there when Emma came bursting in with Cortana in her hand.

Julian was a few paces behind her. They’d agreed it was better not to seem as if they’d been together.

Everyone was standing at the windows, from which the curtains had been thrown back to provide an uninterrupted view of the courtyard and the front of the Institute. Magnus was leaning against the glass, arm extended, hand flat against the pane, his expression grim. There were black hollows under his eyes and he looked worryingly gaunt and exhausted.

Mark and Kieran came in as Emma hooked her sword over her back and hurried to the windows. Julian slid in beside her and stared through the glass.

The five Riders hadn’t moved from the courtyard. They remained where they were, like statues. Their horses had no reins or bridles, nothing for them to hold. They sat with their swords unsheathed, held out ahead of them like a row of gleaming teeth.

Kieran came forward before Mark, crossing the room to the window, and after a moment Mark followed. They stood in a line: the Shadowhunters, the warlock, and the faerie prince, staring grimly down at the courtyard. Kieran was silent and sick-looking, his hair a pale white, the color of bones.

“They can’t get inside the Institute,” said Ty.

“No,” Magnus said. “The wards keep them out.”

“Nonetheless, we should get away as soon as we can,” said Kieran. “I do not trust the Riders. They will think of some way in.”

“We need to contact Alicante,” said Livvy. “Get them to open their side of a Portal so we can get out of here.”

“We can’t do that without revealing that the Riders are here, and why,” said Julian. “But—we could still Portal away from here, even if we didn’t go straight to Idris.” He glanced sideways at Magnus.

“The thing is, I can’t make my side of a Portal right now,” said Magnus. He spoke with some effort. “We need to hold out a few hours. I’ve exhausted my energy—I wasn’t expecting to need to heal Kit, or to need to send Alec and the children away.”

There was an awful silence. It had never occurred to any of them that there were things Magnus couldn’t do. That he had weaknesses, like anyone else.

“There’s a Portal in the crypt,” said Ty. “But it only goes to the Cornwall Institute.”

No one asked him how he knew that. “That Institute is abandoned, though,” said Julian. “The protections are probably stronger here.”

“We’d just be trading Institute for Institute,” said Magnus. “We’d still be trapped inside, and with weaker protections. And believe me, they’d be able to follow us. There have never been greater hunters than the Riders of Mannan.”

“What about Catarina Loss?” said Livvy. “She got us out of the Los Angeles Institute.”

Magnus took a shaky breath. “The same wards keeping the Riders out also prevent anyone from trying to make a Portal from outside.”

“What about the Seelie Queen?” Emma said. “Might she be willing to help us fight the Riders?”

“The Queen isn’t on our side,” said Julian. “She’s only on her own side.”

There was a long silence. Magnus broke it. “I have to hand it to you,” he said. “I never thought Jace and Clary would be topped by anyone else in terms of insane, self-destructive decisions, but you all are giving them a run for their money.”

“I really had nothing to do with this,” Kieran pointed out stiffly.

“I think you will find many poor decisions led you here, my friend,” Magnus said. “All right, there are a few things I can do to try to bring my energy up. You—all of you—wait here. And don’t do anything stupid.”

He strode out of the room on long, black-clad legs, swearing under his breath.

“He’s getting more and more like Gandalf,” said Emma, watching him go. “I mean, a hot, younger-looking Gandalf, but I keep expecting him to start stroking his long white beard and muttering darkly.”

“At least he’s willing to help us,” said Julian. His gaze sharpened. A Rider was coming through the gates. The sixth rider, this one with a slighter build, a spill of long bronze hair. Ethna, Emma thought. The sister.

Then her thoughts dissolved into a buzz of shock. A small figure was propped on the bronze horse’s back in front of her. A little human girl, with short black hair. She dangled limply in the faerie woman’s one-handed grip, but she was blinking, her face twisted in terror. She couldn’t have been more than four years old—she wore leggings with a cheerful print of bees, and bright pink sneakers.

In her other hand, Ethna held a dagger, the point of it against the back of the girl’s neck.

Julian had gone rigid as marble, his face white. Voices rose around Emma in the room, but they were only noise. She couldn’t distinguish the words. She was staring at the little girl, and in her mind she saw Dru, Tavvy, even Livvy and Ty; they had all been that tiny once, that helpless.

And Ethna was strong. All she had to do was drive that dagger forward, and she’d sever the child’s head from her neck.

“Get back from the window,” said Julian. “Everyone, get back from the window. If they don’t think we’re watching them, they’re less likely to hurt the girl.”

His hand was on Emma’s arm. She staggered back with the others. She could hear Mark protesting. They should go down, he was saying. Fight off the Riders.

“We can’t,” said Julian in anguish. “We’ll be slaughtered.”