“Centurions?” Panic flashed in Julian’s eyes, a look of fear and vulnerability that Emma guessed was visible only to her. It was gone almost instantly. “Why?”

Centurions. Elite Shadowhunters, they trained at the Scholomance, a school carved into the rock walls of the Carpathian Mountains, surrounded by an icy lake. They studied esoteric lore and were experts in faeries and the Cold Peace.

And also, apparently, sea demons.

“This is excellent news,” said Perfect Diego. He would say that, Emma thought. Smugly, he touched the pin at his shoulder. “They will be able to find the body and the book.”

“Hopefully,” Clary said.

“But you’re already here, Clary,” said Julian, his voice deceptively mild. “You and Jace—if you brought in Simon and Isabelle and Alec and Magnus, I bet you could find the body right away.”

He doesn’t want strangers here, Emma thought. People who would pry into the Institute’s business, demand to talk to Uncle Arthur. He had managed to preserve the Institute’s secrets even through everything that had happened with Malcolm. And now they were threatened again by random Centurions.

“Clary and I are only stopping by,” Jace said. “We can’t stay and search, though we’d like to. We’re on assignment from the Council.”

“What kind of assignment?” Emma said. What mission could be more important than retrieving the Black Volume, clearing up the mess Malcolm had made once and for all?

But she could tell from the look that Jace and Clary exchanged that there was a world of more important things out there, ones she couldn’t imagine. Emma couldn’t help a small explosion of bitterness inside, the wish that she were just a bit older, that she could be equal to Jace and Clary, know their secrets and the Council’s secrets.

“I’m so sorry,” Clary said. “We can’t say.”

“So you’re not even going to be here?” Emma demanded. “While all this is going on, and our Institute is invaded—”

“Emma,” Jace said. “We know that you’re used to being alone and untroubled here. To having only Arthur to answer to.”

If only he knew. But that was impossible.

He went on, “But the purpose of an Institute is not just to centralize Clave activity, but to house Shadowhunters who must be accommodated in a city they don’t live in. There are fifty rooms here that no one is using. So unless there’s a pressing reason they can’t come . . .”

The words hung in the air. Diego looked down at his hands. He didn’t know the full truth about Arthur, but Emma guessed that he suspected.

“You can tell us,” Clary said. “We’ll keep it in the strictest confidence.”

But it wasn’t Emma’s secret to tell. She held herself back from looking at Mark or Cristina, Diana or Julian, the only others at the table who knew the truth about who really ran the Institute. A truth that would need to be hidden from the Centurions, who would be duty-bound to report it to the Council.

“Uncle Arthur hasn’t been well, as I assume you know,” Julian said, gesturing toward the empty chair where the Institute’s head would normally have sat. “I was concerned the Centurions might worsen his condition, but considering the importance of their mission, we’ll make them as comfortable as possible.”

“Since the Dark War, Arthur has been prone to flare-ups of headaches and pain in his old wounds,” added Diana. “I’ll run interference between him and the Centurions until he’s feeling better.”

“There’s really nothing to worry about,” said Diego. “They’re Centurions—disciplined, orderly soldiers. They won’t be throwing wild parties or making unreasonable demands.” He put an arm around Cristina. “I’ll be glad to have you meet some of my friends.”

Cristina smiled back at him. Emma couldn’t help but glance toward Mark to see if he was looking at Cristina and Diego the way he often did—a way that made her wonder how Julian could miss it. One day he would notice, and there would be awkward questions to answer.

But that day wouldn’t be today, because sometime in the past few minutes Mark had slipped soundlessly out of the library. He was gone.

*

Mark associated different rooms in the Institute with different feelings, most of them new since his return. The rowaned library made him tense. The entryway, where he had faced down Sebastian Morgenstern so many years ago, made his skin prickle, his blood heat.

In his own room he felt lonely. In the twins’ rooms, and Dru’s or Tavvy’s, he could lose himself in being their older brother. In Emma’s room he felt safe. Cristina’s room was barred to him. In Julian’s room, he felt guilty. And in the training room, he felt like a Shadowhunter.

He had made unconsciously for the training room the moment he’d left the library. It was still too much for Mark, the way that Shadowhunters hid their emotions. How could they bear a world where Helen was exiled? He could hardly bear it; he yearned for his sister every day. And yet they all would have looked at him in surprise if he had cried out in grief or fallen to his knees. Jules, he knew, didn’t want the Centurions there—but his expression had hardly changed. Faeries could riddle and cheat and scheme, but they did not hide their honest pain.

It was enough to send him to the weapons rack, his hands feeling for whatever would let him lose himself in practice. Diana had owned a weapons shop in Idris once, and there was always an impeccable array of beautiful weapons laid out for them to train with: Greek machaera, with their single cutting edges. There were Viking spatha, two-handed claymores and zweih?nder, and Japanese wooden bokken, used only for training.

He thought of the weapons of faerie. The sword he had carried in the Wild Hunt. The fey used nothing made of iron, for weapons and tools of iron made them sick. The sword he had borne in the Hunt had been made of horn, and it had been light in his hand. Light like the elf-bolts he had shot from his bow. Light like the wind under the feet of his horse, like the air around him when he rode.

He lifted a claymore from the rack and turned it experimentally in his hand. He could feel that it was made of steel—not quite iron, but an iron alloy—though he didn’t have the reaction to iron that full-blooded faeries did.

It did feel heavy in his hand. But so much had been feeling heavy since he had returned home. The weight of expectation was heavy. The weight of how much he loved his family was heavy.

Even the weight of what he was involved in with Emma was heavy. He trusted Emma. He didn’t question that she was doing the right thing; if she believed it, he believed in her.

But lies didn’t come to him easily, and he hated lying to his family most of all.

“Mark?” It was Clary, followed by Jace. The meeting in the library must be over. They had both changed into gear; Clary’s red hair was very bright, like a splash of blood against her dark clothes.

“I’m here,” Mark said, placing the sword he’d been holding back in the rack. The full moon was high, and white light filtered through the windows. The moon traced a path like a road across the sea from where it kissed the horizon to the edge of the beach.

Jace hadn’t said anything yet; he was watching Mark with hooded golden eyes, like a hawk’s. Mark couldn’t help but remember Clary and Jace as they had been when he’d met them just after the Hunt had taken him. He’d been hiding in the tunnels near the Seelie Court when they’d come walking toward him, and his heart had ached and broken to see them. Shadowhunters, striding through the dangers of Faerie, heads held high. They were not lost; they were not running. They were not afraid.

He had wondered if he would have that pride again, that lack of fear. Even as Jace had pressed a witchlight into his hand, even as he had said, Show them what a Shadowhunter is made of, show them that you aren’t afraid, Mark had been sick with fear.

Not for himself. For his family. How would they fare in a world at war, without him to protect them?