For the rock floor ended in a sheer drop. He was standing on an outcropping, looking down at a round amphitheater. It was full of automatons. They were silent, unmoving and still, like mechanical toys that had wound down. They were dressed, as those in the village had been, in scraps of military uniforms, lined up one by one, for all the world like life-size lead soldiers.

In the center of the room was a raised stone platform, and on the table lay another automaton, like a corpse on an autopsy table. Its head was bare metal, but there was pale human skin stretched taut over the rest of its body-and on that skin was inked runes.

As he stared, Will recognized them, one after another: Memory, Agility, Speed, Night Vision. They would never work, of course, not on a contraption made of metal and human skin. It might fool Shadowhunters from a distance, but ...

But what if he used Shadowhunter skin? a voice in Will's mind whispered. What could he create then? How mad is he, and when will he stop? The thought, and the sight of the runes of Heaven inscribed on such a monstrous creature, twisted Will's stomach; he jerked away from the edge of the outcropping and stumbled back, fetching up against a cold rock wall, his hands clammy with sweat.

He saw the village again in his mind, the dead bodies in the streets, heard the mechanical hiss of the clockwork demon as it spoke to him:

All these years you have driven us from this world with your runed blades. Now we have bodies that your weapons will not work on, and this world will be ours.

Rage poured through Will like fire in his veins. He tore himself away from the wall and plunged headlong down a narrow tunnel, away from the cavern room. As he went, he thought he heard a sound behind him-a whirring, as if the mechanism of a great watch were starting up-but when he turned, he saw nothing, only the smooth walls of the cave, and the unmoving shadows.

The tunnel he was following narrowed as he walked, until eventually he was squeezing sideways past an outcropping of quartz-laden rock. If it narrowed further, he knew, he would have to turn around and go back to the cavern; the thought made him push himself forward with renewed vigor, and he slid forward, almost falling, as the passage suddenly opened into a wider corridor.

It was almost like a hallway at the Institute, only made all of smoothed stone, with torches at intervals set into metal brackets. Beside each torch was an arched door, also of stone. The first two stood open on empty dark rooms.

Beyond the third door was Tessa.

Will did not see her immediately when he walked into the room. The stone door swung partly shut behind him, but he found that he was not in darkness. There was a flickering light-the dimming flames of a blaze in a stone fireplace at the far end of the room. To his astonishment it was furnished like a room in an inn, with a bed and washstand, rugs on the ground, even curtains on the walls, though they hung over bare stone, not windows.

In front of the fire was a slim shadow, crouched on the ground. Will's hand went automatically to the hilt of the dagger at his waist-and then the shadow turned, hair slipping over her shoulder, and he saw her face.

Tessa.

His hand fell away from the dagger as his heart lurched inside his chest with an impossible, painful force. He saw her expression change: curiosity, astonishment, disbelief. She rose to her feet, her skirts tumbling around her as she straightened, and he saw her hold her hand out.

"Will?" she said.

It was like a key turning the lock of a door, releasing him; he started forward. There had never been a greater distance than the distance that separated him from Tessa at that moment. It was a large room; at the moment, the distance between London and Cadair Idris seemed nothing to the distance across it. He felt a shudder, as of some sort of resistance, as he crossed the room. He saw Tessa hold out her hand, her mouth shaping words-and then she was in his arms, the breath half-knocked out of both of them as they collided with each other.

She was up on her toes, her arms around his shoulders, whispering his name: "Will, Will, Will-" He buried his face against her neck, where her thick hair curled; she smelled of smoke and violet water. He clutched her even more tightly as her fingers curled against the back of his collar, and they clung together. For just that moment the grief that had clenched him like an iron fist since Jem's death seemed to relax and he could breathe.

He thought of the hell he had been in since he'd left London-the days of riding without stopping, the sleepless nights. Blood and loss and pain and fighting. All to bring him here. To Tessa.

"Will," she said again, and he looked down into her tearstained face. There was a bruise across her cheekbone. Someone had hit her there, and his heart swelled with rage. He would find out who it was, and he would kill them. If it was Mortmain, he would kill him only after he had burned his monstrous laboratory to the ground, that the madman might see the ruin of all his creation-"Will," Tessa said again, interrupting his thoughts. She sounded almost breathless. "Will, you idiot."

His romantic notions came to a screeching halt like a hackney cab in traffic on Fleet Street. "I- What?"

"Oh, Will," she said. Her lips were trembling; she looked as if she couldn't decide whether to laugh or cry. "Do you remember when you told me that the handsome young gentleman who came to rescue you was never wrong, not even if he said the sky was purple and made of hedgehogs?"

"The first time I ever saw you. Yes."

"Oh, my Will." She drew gently away from his embrace, smoothing a tangled lock of hair behind her ear. Her eyes remained fixed on his. "I cannot imagine how you came to find me, how difficult it must have been. It is incredible. But-do you really think Mortmain would leave me unguarded in a room with an open door?" She turned away and moved a few feet forward, then stopped abruptly. "Here," she said, and raised her hand, spreading her fingers wide. "The air is as solid as a wall here. This is a prison, Will, and now you are in it alongside me."

He moved to stand beside her, already knowing what he would find. He recalled the resistance he had felt as he crossed the room. The air rippled slightly when he touched it with his finger but was harder than a frozen lake. "I know this configuration," he said. "The Clave uses a version of it sometimes." His hand curled itself into a fist, and he slammed it against the solid air, hard enough to bruise the bones in his hand. "Uffern gwaedlyd," he swore in Welsh. "All the bloody way across the country to get to you, and I can't even do this right. The moment I saw you, all I could think of was running to you. By the Angel, Tessa-"

"Will!" She caught at his arm. "Don't you dare apologize. Do you understand what it means to me that you are here? It is like a miracle or the direct intervention of Heaven, for I had been praying to see the faces of those I cared for again before I died." She spoke simply, straightforwardly-it was one of the things he had always loved about Tessa, that she did not hide or dissemble, but spoke her mind without embellishment. "When I was in the Dark House, there was no one who cared enough to search for me. When you found me, it was an accident. But now-"

"Now I have condemned us both to the same fate," he said in a low voice. He drew a dagger from his belt and drove it against the invisible wall before him. The runed silver blade of the dagger shattered, and Will cast the broken hilt aside and cursed again, under his breath.

Tessa put a light hand on his shoulder. "We are not condemned," she said. "Surely you have not come by yourself, Will. Henry, or Jem, will find us. From the other side of the wall, we can be freed. I have seen how Mortmain does it, and ..."

Will did not know what happened then. His expression must have changed at the mention of Jem's name, for he saw some of the color leave her face. Her hand tightened on his arm.

"Tessa," he said. "I am alone."

The word "alone" came out broken, as if he could taste the bitterness of loss on his tongue and struggled to speak around it.

"Jem?" she said. It was more than a question. Will said nothing; his voice seemed to have fled. He had thought to spirit her from this place before he told her about Jem, had imagined telling her somewhere safe, somewhere where there would be space and time to comfort her. He knew now he had been a fool to think it, to imagine that what he had lost would not be written all over his face. The remaining color drained from her skin; it was like watching a fire flicker and go out. "No," she whispered.

"Tessa ..."

She took a step back from him, shaking her head. "No, it's not possible. I would have known-it can't be possible."

He reached out a hand to her. "Tess-"

She had begun to shake violently. "No," she said again. "No, don't say it. If you don't say it, it won't be true. It can't be true. It isn't fair."

"I'm sorry," he whispered.

Her face crumpled, shattered like a dam under too much pressure. She sank to her knees, folding in on herself. Her arms went around her body. She was holding herself tightly, as if she could keep from breaking apart. Will felt a fresh wave of the helpless agony he had experienced in the courtyard of the Green Man. What had he done? He had come here to save her, but instead of saving her he had only succeeded in inflicting agony. It was as if he were truly cursed-capable only of bringing suffering to those he loved.

"I am sorry," he said again, with all his heart in the words. "So sorry. I would have died for him if I could."

At that, she looked up. He braced himself for the accusation in her eyes, but it was not there. Instead she reached up her hand to him silently. In wonder and surprise he took it, and let her draw him down until he was kneeling opposite her.

Her face was streaked with tears, surrounded by the tumble of her hair, outlined in gold by the firelight. "I would have too," she said. "Oh, Will. This is all my fault. He threw away his life for me. If he had taken the drug more sparingly-if he had allowed himself to rest and be ill instead of pretending good health for my sake-"

"No!" He took her by the shoulders, turning her toward him. "It's not your fault. No one could imagine that it was-"

She shook her head. "How can you bear to have me near you?" she said in despair. "I took your parabatai from you. And now we will both die here. Because of me."

"Tessa," he whispered, shocked. He could not remember the last time he had been in this position, the last time he had had to comfort someone whose heart was broken, and had genuinely been allowed to, rather than forcing himself to turn away. He felt as clumsy as he had as a child, dropping knives from his hands before Jem had taught him how to use them. He cleared his throat. "Tessa, come here." He drew her toward him, until he was sitting on the ground and she was leaning against him, her head on his shoulder, his fingers threading through her hair. He could feel her body shaking against him, but she did not pull away. Instead she clung to him, as if truly his presence gave her comfort.

And if he thought of how warm she was in his arms or the feel of her breath on his skin, it was only for a moment, and he could pretend that it wasn't at all.

Tessa's grief, like a storm, spent itself slowly over the course of hours. She wept, and Will held her and did not let go, except for once when he rose and built up the fire. He returned swiftly and sat down beside her again, their backs against the invisible wall. She touched the place on his shoulder where her tears had soaked through the fabric.

"I'm sorry," she said. She couldn't count the number of times she'd told him she was sorry over the past hours, as they'd shared the tales of what had happened to them since their separation at the Institute. He'd spoken to her of his farewell to Jem and Cecily, his ride across the countryside, the moment he had realized Jem was gone. She'd told him of what Mortmain had demanded of her, that she Change into his father, and give him the last bit of the puzzle that would turn his automaton army into an unstoppable force.

"You have nothing to be sorry for, Tess," Will said now. He was looking toward the fire, the only light in the room. It painted him in shades of gold and black. The shadows under his eyes were violet, the angle of his cheekbones and collarbones sharply outlined. "You have suffered, just as I have. Seeing that village destroyed-"

"We were both there at the same time," she said, wonderingly. "If I had known you were near-"

"If I had known you were near, I would have charged Balios directly up the hill to you."

"And been murdered by Mortmain's creatures in the process. It is better that you did not know." She followed his gaze to the fire. "You found me in the end; that is what matters."

"Of course I found you. I promised Jem I would find you," he said. "Some promises cannot be broken."

He took a shallow breath. She felt it against her side: she was curled half against him, and his hands were shaking, almost imperceptibly, as he held her. Distantly she knew that she should not let herself be held like this by any boy who was not her brother or fiance-but her brother and her fiance were both dead, and tomorrow Mortmain would find them and punish them both. She could not bring herself, in the face of all that, to care much about propriety.

"What was the point of all that pain?" she asked. "I loved him so much, and I wasn't even there when he died."

Will's hand smoothed down her back-light and quick, as if he were afraid she would draw away. "Neither was I," he said. "I was in the courtyard of an inn, halfway to Wales, when I knew. I felt it. The bond between us being severed. It was as if a great pair of scissors had cut my heart in half."

"Will ...," Tessa said. His grief was so palpable, it mixed with her own to create a sharp sadness, lighter for being shared, though it was hard to say who was comforting who now. "You were always half his heart as well."

"I am the one who asked him to be my parabatai," Will said. "He was reluctant. He wanted me to understand that I was tying myself in what was meant to be a life bond to someone who would not live much of a life. But I wanted it, blindly wanted it, some proof that I wasn't alone, some way to show him what I owed him. And he gave way gracefully to what I wanted in the end. He always did."

"Don't," said Tessa. "Jem wasn't a martyr. It was no punishment for him, being your parabatai. You were like a brother to him-better than a brother, for you had chosen him. When he spoke of you, it was with loyalty and love, unclouded by any doubt."

"I confronted him," Will went on. "When I found he had been taking more of the yin fen than he should. I was so angry. I accused him of throwing his life away. He said, 'I can choose to be as much for her as I can be, to burn as brightly for her as I wish.'"