“Lottie,” Alistair said, blocking the doorway. “What are you doing up here?”

“Have you seen Uncle Leander?” she asked him, twisting her hands. “He was supposed to take Jamie and me to town for the day.”

I wondered how, exactly, one lied to a Holmes; I’d never successfully done it myself. Could you actually pull it off if you were one, too?

From the withering look Alistair gave his daughter, I decided you couldn’t.

“He left last night. One of his contacts in Germany was growing suspicious of his continued absence.” He waved an errant hand. “Of course, he said he loves you, wishes you well, et cetera.”

There was a rustle, and Holmes’s father flung an arm across the door. “Mum?” Holmes asked, trying to step around him. “Is she in there? I thought she’d be in her room.”

“Don’t,” he said. “She’s having a very bad day.”

“But I—” And she ducked under his outstretched arm and into his study.

The hospital bed was nowhere to be found. I hadn’t seen Emma Holmes in days and had assumed she’d been in her room, but here she was, flung out on the sofa like she’d fallen there. Her ash-blond hair hung limply around her face, and she was wearing a robe not unlike her daughter’s, thrown over a set of pajamas that looked wrinkled and sour. As I opened my mouth, she held up a hand. I glanced over at Holmes, who stiffened.

This house was nothing like my family’s flat, where you tripped over each other on your way to the bathroom. Here, you could go weeks and see only pale marble floors, floating staircases, invisible plastic chairs. You could start to believe you were the only person in the world.

“What are your plans for Christmas?” her mother asked abruptly. Her voice came out in a harsh whisper.

“I—”

“I’m speaking to my daughter.” But she was looking at Alistair, and with anger. It must have been terrible to be this way, prone and weak, when you were used to commanding the room.

Alistair cleared his throat. “Lottie, your brother has just expressed an interest in you staying in Berlin for the holiday.”

“Oh,” Holmes said, stuffing her hands in her pockets. I could hear the machinery in her brain grinding to life. “Has he.”

“Don’t exhaust your mother,” he said. “We can have a rational conversation about this.”

“She has to go.” Emma struggled up to her elbows, like a scuttling crab. Her breathing was labored.

“She doesn’t,” Alistair murmured. He made no motion to help her. “I’d rather have Lottie here. We never see her.”

Holmes looked horrified, but her voice was calm. “Milo hasn’t spoken to you in weeks,” she said. “You haven’t had that twitch you get, on the side of your mouth, after you talk to him.”

“I’ve been ill,” her mother said, as if it wasn’t obvious. “That’s enough to change anyone’s tells.”

“Yes,” her daughter said, plowing ahead. “But the doctor you brought in—Dr. Michaels, from Highgate Hospital—doesn’t specialize in fibromyalgia. She specializes in—”

“Poisons,” her mother said.

At that, Alistair turned on his heel and retreated into the hall, snapping the door shut behind him.

Poisons?

“She also specializes in nanotechnology,” Holmes was murmuring, but it was clear her brain had run ahead of her emotions. Then: “Oh, God, Mum. Poison? But I hadn’t noticed any signs, I should have—I never wanted—”

Her mother’s eyes burned. “You might have thought of that before you interfered with Lucien Moriarty.”

Dizzily, I leaned against the wall. I still dreamt about it, what had happened to me that fall. The poison spring. The fever. The hallucinations. It hadn’t been a poisoning so much as a purposeful infection, but Bryony Downs had still made me into a pale, helpless wreck. I couldn’t imagine what Emma Holmes was feeling.

“Where is Leander?” Holmes asked, squaring her shoulders. “Why on earth would he go without telling me good-bye?”

I braced myself for the reaction. But the fire had already gone out in her mother’s eyes, and her face was gray again. You could see the veins in her forehead. I remembered the photograph I’d seen of her, all turned out in a black suit, her lips a dark, dark red, power crackling off her like a cut wire. I couldn’t square it with the exhausted woman in front of me. Poisoned, I thought. My God. She must’ve taken a leave of absence from work. What had Holmes said she’d done again? Wasn’t she a scientist?

“That isn’t the issue at hand,” Emma Holmes said. She shut her eyes to concentrate on the words.

“You’re telling me that Leander has snuck out like a fugitive, apparently days after you’ve been poisoned, and there’s nothing to worry about?” She turned to the study door. “That this was all part of the plan? What on earth is happening?”

“We’ve tracked the poisoning back to the day you arrived; it was an isolated event, and we’re taking precautions. We’re controlling what we eat, what we breathe. We’re culling the staff. We’ll figure it out soon enough. But for now . . . Lottie, for your safety, there is no way you and Jamie can continue to stay here. I’ve transferred funds into your account for the trip. Go see your brother. Get out of this house.” With that, she lifted a hand as if to touch her daughter, but Holmes ignored it. Her back had gone straight and still. Her eyes narrowed.