Sister Emilia will take the adamas, Brother Zachariah said. And once you’ve given it to her, you will send the Market away because I ask it of you.

“If I do so, will that cancel out the favor I owe you?” Belial said.

“He owes you a favor?” Sister Emilia said. She thought, No wonder they stitch up the Silent Brothers’ mouths. They have so many secrets.

It will not, Brother Zachariah said to Belial. To Emilia, he said, Yes, and that is why you need not be afraid of him. A demon cannot kill one it is indebted to.

“I could kill her, though,” Belial said. He took a step toward Sister Emilia, and she raised her sword, determined to make her death count.

But you won’t, Brother Zachariah said calmly.

Belial raised an eyebrow. “I won’t? Why not?”

Brother Zachariah said, Because you find her interesting. I certainly find her so.

Belial was silent. Then he nodded. “Here.” He threw the mask at Sister Emilia, who let go of Brother Zachariah’s hand to catch it. It was lighter than she would have expected. “I imagine they won’t let you work it, though. Too worried I might have corrupted it in some way. And who is to say that I didn’t?”

We’re done, Brother Zachariah said. Go from here and do not return.

“Absolutely!” Belial said. “Only, about that favor. It pains me so to be in debt to you when I might be of some service. I wonder if there isn’t a thing that I could offer you. For example, the yin fen in your blood. Do the Silent Brothers still not know what the cure might be?”

Brother Zachariah said nothing, but Sister Emilia could see how his knuckles grew white where his fist was clenched. At last he said, Go on.

“I might know a cure,” Belial said. “Yes, I think I know a sure cure. You could be who you once were. You could be Jem again. Or.”

Brother Zachariah said, Or?

Belial’s long tongue flicked out, as if he was tasting the air and found it delicious. “Or I could tell you a thing you don’t know. There are Herondales, not the ones you know, but of the same bloodline as your parabatai. They are in great danger, their lives hang by a thread, and they are closer to us as we stand here than you can imagine. I can tell you something of them and set you on the path to find them if that is what you choose. But you must choose. To aid them or else to be who you once were. To once more be the one who left behind those who loved him best. The one they still yearn for. You could be him again if that is what you choose. Choose, Brother Zachariah.”

Brother Zachariah hesitated for a long moment.