James drew away enough to look down into her face. “What happened?” he said. “Your letter said you were in danger.”

She dropped a hand now to circle his wrist, her fingers sliding over the band of metal as if to make sure it was still there. Her fingers pressed against his pulse point. “Mama is mad with rage. I don’t know what she will do. She told Charles—”

“I know what she told Charles,” he said. “Please tell me you were not worried about me, Grace.”

“You came to the house to see me,” she said. “Did you know that Cordelia was there?”

He hesitated. How could he say that he hadn’t come to the house to see her? That there had been a moment—a terrible moment—when Cordelia had mentioned that Grace was in the house, and he’d realized he had not thought of her? How was it possible to feel such agony when someone’s name was mentioned, yet forget them in duress? He recalled Jem having told him that stress could do terrible things to one’s mind. Surely that was all it was.

“I didn’t know until I arrived and saw her and Lucie,” he said. “I gather they wanted to see that you were all right. When I came, I heard the noises in the greenhouse, and—” He broke off with a shrug. He hated lying to Grace. “I saw the demon.”

“You were being brave, I know, but Mama does not see it that way. She thinks you came only to humiliate her and remind the world of her father’s misdeeds.”

James badly wanted to kick a lamppost. “Let me talk to her. We could sit down, all of us, my father and you and your mother—”

“James!” Grace looked almost furious for a moment. “What my mother would do to me if I even suggested such a thing—” She shook her head. “No. She watches everything I do. I was barely able to get out tonight. I had thought that coming to London might soften her toward you, but she has become harder than ever. She says the last time Herondales were at Chiswick House, her father and husband died. She says she will not let you destroy us.”

Tatiana is utterly mad, James thought helplessly. He had not realized it had gone so much beyond spite. “Grace, what are you saying?”

“She says she will bring me back to Idris. That she was wrong to let me attend parties and events that you and your sister would be at, and the Lightwoods—she says that I will be corrupted and ruined. She will lock me away, James, for the next two years. I will not see you, not be able to write to you—”

“That is the danger you meant,” he said softly. He understood. Such loneliness would seem like danger to Grace. It would seem like death. “Then come to us at the Institute,” he said. “The Institute is there to provide sanctuary to Nephilim in distress. My parents are kind people. We would protect you from her—”

Grace shook her head hard enough to dislodge her small, flower-trimmed hat. “My mother would only petition to have the Clave return me to her, and they would do it as I am not eighteen yet.”

“You don’t know that. My parents have influence within the Clave—”

“If you truly love me,” she said, her gray eyes flaring, “then you will marry me. Now. We must elope. If we were mundanes, we could run to Gretna Green and marry, and nothing could tear us apart. I would belong to you, and not to her.”

James was stunned. “But we are not mundanes. Their marriage ceremony would not be considered valid by the Clave. Marry me in a Shadowhunter ceremony, Grace. You don’t need her permission—”

“We cannot do that,” Grace protested. “We cannot remain in the Shadowhunter world where my mother can reach us. We must escape her influence, her ability to punish us. We must be married in Gretna and if needs be, we will let our Marks be stripped.”

“Let our Marks be stripped?” James went cold all over. Having your Marks stripped was the most severe punishment a Shadowhunter could endure. It meant exile and becoming a mundane.

He tried to imagine never seeing his parents again, or Lucie, or Christopher or Thomas. Having the bond that tied him to Matthew severed, like having his right hand sliced off. Becoming a mundane and losing everything that made him a Shadowhunter. “Grace, no. That isn’t the answer.”

“It isn’t the answer for you,” she said coolly, “for you have always been a Shadowhunter. I have never been trained, never borne but a few Marks. I know nothing of the history, I have no warrior partner nor friends—I might as well have been raised a mundane!”

“In other words,” said James, “you would be losing nothing, and I would be losing everything.”

Grace stepped out of James’s arms. Pain took her place, the ache of being without her. It was physical, inexpressible, and unexplainable. It was simply what it was: when she was not there, he felt it like a wound.

“You would not be losing me,” said Grace.

“I don’t want to lose you,” he said, as steadily as he could through the pain. “But we have only to wait a little while and we can be together without also losing everything else.”

“You don’t understand,” Grace cried. “You can’t. You don’t know—”

“Then tell me. What is it? What don’t I know?”

Her voice was hoarse. “I must have you do this for me, James,” she said. “I must. It is so important. More than you can know. Only say you will. Only say it.”

It seemed almost as if she were begging him to say it even if he did not mean it, but what would be the point of that? No. She must want him to mean it. To be willing to do it: risk the end of the only life he knew, risk never seeing any of those he loved again. He closed his eyes and saw, against the backs of his eyelids, the faces of his parents. His sister. Jem. Thomas. Christopher. Matthew. Matthew, who he would be damaging in a way that might never be repaired.

He struggled to say the words, to shape them. When he finally spoke, his voice was as hoarse as if he had been screaming. “No. I cannot do it.”

He saw her flinch back. “This is because you did not come to Idris,” she said, her lips trembling. “At the beginning of this summer. You—you forgot me.”

“I could never have forgotten you. Not after weeks, or months, or years, Grace.”

“Any man would marry me,” she went on. “Any man would do this if I asked him. But not you. You have to be different.” Her mouth twisted. “You are made of different stuff than other men.”

James flung up a hand in protest. “Grace, I do want to marry you—”

“Not enough.” She took a step back from him—then her eyes widened suddenly, and she screamed. James’s body moved faster than thought. He flung himself at Grace and they both hit the pavement hard. Grace gasped and pressed herself against the river wall as a demon shot past them, a hairbreadth away.

And it was a demon. A dark, twisted shape like a mangled tree root, eyeless and noseless but with thorn-sharp brown teeth, its body coated with black slime. It had no wings, but long, bent legs like a frog’s: it sprang at them again, and this time James yanked a blade from his belt and flung it. Runes flashed across the blade like fire as it sailed through the air and struck, nearly blowing apart the demon’s chest. Ichor splattered, and it vanished back to its own dimension.

Grace had scrambled to her feet; he pulled her up the steps and onto the bridge, for a better vantage point. “A Cerberus demon,” she said, blinking. “But it was dead—the one in the greenhouse was dead—that’s why I thought I could leave—” She sucked in her breath. “Oh, God. There are more of them coming.”

She thrust out her hands as if she could push them away. They were coming, indeed: dark shapes were appearing through the fog from the middle of the bridge, crawling and leaping like hellish frog-monsters, slithering and slipping across the wet road. As one hopped toward them, it shot out a long, black, sticky tongue, snatched up an unfortunate pigeon, and deposited the bird into its fanged mouth.

James fired off throwing knives: one, two, three times. Every time, a demon fell. He pressed a knife into Grace’s hand, his eyes entreating her—she backed up against the railing of the bridge, the blade gripped in her shaking hand. A demon reached for her and she stabbed out; it made an eerie howling sound as black-red ichor streamed from its shoulder. It hopped away from her, hissing, and lunged again. She ducked. James flung a knife and destroyed the thing, but he knew he was nearly out of blades. When they were gone, he would have only one weapon left: a seraph blade.

It would not be enough to protect himself and Grace. Nor could they run. The demons would easily catch them.

Two creatures dived for them. James hurled his last blade, dispatching one Cerberus demon in a rain of ichor. The other fell beside it, cloven in two by a dainty throwing axe.

James froze. He knew that axe.

Whirling, he saw Lucie running full tilt toward him from the road. And she was not alone.

Cordelia was there, Cortana gleaming in her hand. Matthew was beside her, armed with Indian chalikars: circular throwing knives edged with razor-sharp steel. Then came Christopher with two crackling seraph blades and Thomas, wielding his bolas. One flick of the ropes, and one twist of Thomas’s powerful arm, and a demon sailed clear off the bridge and into the river.

Alastair Carstairs was also with them. As James stared, he leaped onto the iron railing of the bridge, balancing just as James and Matthew had once done in practice. A long-bladed spear was in his hand. Two sweeps sliced one of the creatures in half. It exploded into nothingness, splattering Alastair with ichor, which struck James as a positive development on two fronts. Alastair leaped down from the railing with a disgusted noise, and charged into the fray.

As the Shadowhunters spread out around them, a cry rose from the demons—a thick, clogged sound. If a corpse rotting in the dirt had a sound, James thought, that was what it would have been. He sprang backward, swung around, and delivered a spinning kick to an oncoming demon. There was a blur of gold, and the demon vanished; James looked up to see Cordelia standing over him, Cortana in her hand. Its blade was smeared with demon blood.