Trust Jules to try to comfort a puppy at a time like this. She braced herself and jumped—the image of the training room flashed behind her eyelids—landing in the overgrown grass with only a slight sting.

“Jules?” she said, coming closer. With a whimper the dog darted away, into the shadows. “He got away.”

“Yeah?” He straightened up, sounding preoccupied. “What do you think he was doing here?”

“I don’t know; I guessed vampire, but Nightshade keeps a pretty tight leash on them and—Jules?” She heard her voice skip upward an octave as she drew close enough to see that he had one hand pressed against his side. His black gear jacket was torn. “Jules? Are you okay?”

He drew his hand away from his side. His palm was a welter of blood, black under the blue LED lighting of the pool. “I’m fine,” he said. He rose to his feet and took a step toward her—and stumbled. “It’s fine.”

Her heart flipped over. He was holding something in his bloody hand, and her insides went cold as she saw what it was. A short metal crossbow bolt, with a wide triangular head like an arrow, wet with blood. He must have pulled it from his side.

You were never, never supposed to pull an arrow out of your skin: It did more damage coming out than going in. Julian knew that.

“What did you do?” Emma whispered. Her mouth had gone dry.

Blood was leaking steadily from the tear in his jacket. “It was burning,” he said. “Not like a normal arrow. Emma—”

He dropped to his knees. His expression was dazed, though he was clearly fighting it. “We need to get out of here,” he said hoarsely. “The shooter might come back, alone or with more—”

His voice choked off and he fell backward, sprawling in the grass. Emma moved faster than she ever had in her life, leaping across the pool, but she still wasn’t there in time to catch him before he hit the ground.

Clouds were gathering out over the ocean. The wind up on the roof was cool, the ocean acting like a giant air conditioner. Cristina could hear the roar and crash of the surf in the distance as she moved gingerly across the shingles. What was it about the Blackthorns and Emma that meant that ever since she’d come to Los Angeles she’d spent half her time on top of buildings?

Mark was sitting near one of the copper gutters, his legs dangling over the side. The wind blew his fair hair around his face. His hands were long and white and bare, bracing him against the roof tiles behind him.

He was holding one of the Institute’s spare cell phones in his hand. It seemed incongruous—it was incongruous, the faerie boy with the long, tangled hair, the tapestry of stars behind him, and the phone in his hand. “I am so sorry, Helen,” she heard him say, and the word echoed with such a depth of love and loneliness that she nearly turned away.

Leaving silently didn’t seem to be an option, though. Mark had heard her approach: He turned slightly, and gestured for Cristina to remain.

She hovered uncertainly. It was Dru who had told her that she would find Mark on the roof, and the others had urged her to go up and see if he was all right. She had wondered if it was really her place, but Ty and Livvy had been absorbed in their translation job, and she’d sensed Dru was afraid of Mark’s harsh words. And it wasn’t as if Tavvy could be sent to fetch his brother down. So with some reluctance, Cristina had climbed the ladder to the roof.

Now that she was here, though, she felt an aching sympathy for the boy perched at the roof’s edge. The look on his face as he spoke to Helen—she couldn’t imagine what it must be like for him, to know there was only one other person in his family quite like him, who shared his blood and heritage, and to know she was separated from him by a cruel and unbreakable Law.

“And I, you, my sister,” Mark said, and let the phone fall from his hand. It was an old-fashioned one, with a screen that flickered and went dark as the call disconnected.

He slid it into a pocket and looked over at Cristina, the clouds casting shadows on his face.

“If you have come to tell me I behaved ill, I already know it,” he said.

“That’s not why I came,” she said, moving closer to him but not sitting down.

“But you agree,” he said. “I behaved ill. I should not have spoken as I did to Julian, especially in front of the little ones.”

Cristina spoke carefully. “I don’t know Julian well. But I do believe he was worried about you, and that’s why he didn’t want you to go with them.”

“I know that,” Mark said, surprising her. “But do you know what it’s like, to have your little brother worry about you as if you were the child?” He raked his fingers through his hair. “I thought, while I was gone, that Helen would be raising them. I never thought it would fall so much upon Julian’s shoulders. I cannot tell if that is why he seems unknowable to me.”

Cristina thought of Julian, of his quiet competence and careful smiles. She remembered saying to Emma in a joking way that perhaps she would fall in love with Julian when she met him. And he had been much more beautiful than she’d thought, than Emma’s blurry photos or vague descriptions had led her to believe. But though she liked him, she doubted she could love him. Too much of him was hidden for that.

“A great deal of him is, I think, locked away,” she said. “Have you seen the mural on the wall of his room? The one of the fairy tale? He is like that castle, I think, surrounded by thorns that he has grown to protect himself. But with time, you can cut those thorns away. I believe you will know your brother again.”

“I don’t know how much time I have,” he said. “If we do not solve their puzzle, the Wild Hunt will reclaim me.”

“Do you want them to?” Cristina asked softly.

He said nothing, only glanced up at the sky.

“Is that why you come up to the roof? Because from here you can see the Hunt if they go by?”

Mark was silent for a long time. Then he said, “I imagine sometimes I can hear them. That I can hear the sound of their hooves against the clouds.”

She smiled. “I like the way you talk,” she said. “It always sounds like poetry.”

“I speak the way I was taught by the Folk. So many years under their tutelage.” He turned his hands over and placed them on his knees. The insides of his wrists were marked by odd, long scars.

“How many years? Do you know?”

He shrugged. “Time is not measured there as it is measured here. I could not say.”

“The years do not show on your face,” she said quietly. “Sometimes you look as young as Julian and sometimes you look as the fey do—ageless.”

Now he looked at her sideways. “You don’t think I look like a Shadowhunter?”

“Do you want to?”

“I want to look like my family,” he said. “I cannot have the Blackthorn coloring, but I can look as much like Nephilim as possible. Julian was right—if I wish to be part of the investigation, I cannot stand out.”

Cristina held back from telling Mark that there was no world in which he didn’t stand out. “I can make you look like a Shadowhunter. If you come downstairs with me.”

He moved as noiselessly on the shingled roof as if he had the padded feet of a cat or as if he were wearing a Soundless rune. He stepped aside to let her lead the way downstairs. Even that was hushed, and when she brushed by him, his skin was cool as night air.