I don’t know who found me shivering in the doorway, or what time of day it was when I was dragged from the barrack to another hut, three doors down. The new block leader introduced herself and assigned me a bunk. I stood at the window, wrapped in a blanket, and stared out at the charcoal sky.

“They’re not coming back.”

I turned from the window to see who had spoken. A girl with jutting-out bones and a pointy nose sat up in her bunk. She was all angles — gangly arms hanging from her narrow shoulders, and a head too large for her pale, thin neck. “We’re all that’s left.” She motioned to the women lying next to her, their eyes empty, their bodies still. My mother wasn’t among them. I turned back to the window. The camp square was deserted, the watchtowers empty. The door of the barrack opposite swung on its hinge. No one was inside. An elderly woman in rags walked between the barracks, her body bent against the wind. An SS officer hurried past.

“Where is everyone? Where’ve they gone?” I asked the girl.

“I don’t know. I was in barrack 12. We were told we were hiking to a factory, so I snuck in here.”

“My sister went with them,” I said. “They were meant to come back last night.” My legs were shaking. I reached for a bunk and sat down.

“There are no factories.” The block leader stood before us, her thin arms crossed over her drooping chest. “The SS are leaving because they know the Red Army is on its way, and they’ve taken everyone with them — everyone who’s still useful to them, anyway. They didn’t clear out the infirmary.” She looked around the room. “Or take us. Probably didn’t think we’d make it.”

“Make it?”

“To the other camps. Word is they’re headed north.”

“Other camps? How far away?”

She looked at me with something resembling sympathy.

“Three days’ walk, maybe four.”

I ran to the door and pushed it open. I staggered outside, pulled off my boots, and stood in my flimsy dress, barefoot in the ankle-deep snow. I let the wind whip my cheeks and the cold seep into my bones. Erika was out there somewhere. She didn’t have boots, a scarf, or mittens. Four days . . . I took one step, then another. My feet grew numb, but I walked on till I couldn’t feel my fingers or my face or the pain in my chest. I walked past the watchtower to the main gate.

A guard stopped me. “You’re the commandant’s girl?”

I nodded dumbly.

“You want to head left, then, not right. Has the commandant sent for you?” He looked confused.

“Yes,” I said. “Yes, he did.”

He looked down at my feet and shook his head. “I can’t deliver you like that. Go find some shoes.”

The villa was deserted. A lone guard stood at the front gate, his eyes on the road, his hand on his gun. There were no cars in the driveway, no guards in the hall. Rosa wasn’t lurking on the stairs, and Ivanka wasn’t at the sink. Mr. Zielinski was gone, too. The house was dark. I crept along the silent corridors and stopped at the open door of the commandant’s study. The desk was empty and the bookshelves bare. I picked up the wastepaper basket.

“There’s nothing in there. I already checked.”

I spun around. Karl was standing in the hallway. He grabbed my hand and pulled me to the music room.

“My father’s gone to Kraków. They’ve all left.” He reached for the drapes and pulled them apart. “Except for him,” he said, pointing to the guard at the gate.

“You knew, didn’t you?” I stepped toward him.

“I tried to tell you yesterday.”

“You should have. I could’ve done something for Erika.” I stood in front of him. “You could’ve done something. . . .” Karl hung his head. “You’re the commandant’s son. You can do whatever you want.” He didn’t answer. “You say you hate the war.” My temper flared. “But I don’t believe you!” I knew that what I said made no sense, but it felt good to fight back. Good to blame someone other than myself.

“I tried. I’m sorry.” His voice was so low, it was almost a whisper.

“No, you’re not,” I said. “If you were sorry, you’d be out there doing something to get her back.” I grabbed his shirt. “It’s not too late. You could get a car and a driver. You could find out where they are.” I was still holding on to his shirt, the cotton crushed between my fingers, my hands balled against his chest. “She’s all I have left.” I slumped against him. “You have to help. You have to save her.” The sky sparked white, and the windows rattled. Karl looked at me and shook his head.

“I can’t.”

“Can’t?” I ran from the room. I flung the front door open and stepped onto the porch. It was bitterly cold, but I couldn’t go back inside, not with Erika out there. I ran onto the road and tramped through the snow, sinking deeper into the drifts with each step. The villa disappeared and then the street signs, too. I stood in the blinding white, tears dripping from my chin, not knowing whether to head left or right. I didn’t see Karl until he was by my side. His hair was speckled with snow, his shirt wet.

“Come inside,” he begged, pulling me to him.

I didn’t take his hand, but I followed him home. I sat at the piano without opening the lid, facing away from him, too exhausted to speak. I didn’t know what to say, so I didn’t say anything. I didn’t know what to do, so I sat there, mute.

Karl set a cup of tea down on the table beside me and draped a blanket over my legs.

“I can go.” His words said one thing; his face another. I nodded. I didn’t want to talk. My sister was out there, either walking through a snowstorm or buried under one. I kicked off the blanket and pushed the tea away. Karl’s shoulders slumped. He picked up the blanket and walked out of the room.

“I’m sorry, I know you don’t want company,” Karl peered in from the hallway. It might have been an hour later. Maybe more. Time had spun away from me. “My father called. He won’t be back for two days.”

I looked at him blankly.

“You don’t have to stay.”

I stood to leave.

“Or you could stay. We could look in the kitchen for something to eat.” He looked down at the dirty cup hooked to my belt.

“No,” I said, though my stomach was rumbling. “I need to get back.” I stood and walked to the door. I couldn’t stay here by the fire when Erika was out there.

“The Russians are close.” Karl followed me. “The SS are dismantling the camp and heading west.” I stopped at the door. “I heard my father on the telephone. The prisoners left by train. Maybe your sister’s with them.” I let go of the doorknob. They went by train. If Erika made it to the train station, she might still be alive.

“Can I show you something?” Karl spoke quickly. “In my room?”

I hesitated. Karl glanced at the door. “It’s locked. The guard can’t come in.”

I followed him up the stairs. In all my time at the villa, I’d never risked going up the stairs. Karl stopped at a door and turned the handle. Stepping over the threshold was like being sucked back to the past. It was like stepping into my own room and my life before the war. There was an open fire, a Persian rug, and a leather armchair, just like Papa’s. There was a double bed and a wooden bookcase and an upright piano pushed against a wall.

“An August Förster!” I ran to the piano and threw open the lid. “I had one just like it at home.” I sat down and ran my fingers over the keys, lingering at middle C. Karl sat down beside me, his leg resting against mine. I lifted my hands to the keys and played the opening bars of Erika’s favorite piece, Ravel’s Gaspard de la Nuit, and when Karl touched the keys, I shifted my hands up an octave and we played together. It was like dancing a waltz, as intimate as if we’d been running our fingers along each other’s bodies, caressing skin instead of ivory.

“Thank you,” I said when the song ended.

“For what?”

“For seeing me, when it would have been so easy to only see this. . . .” I looked down at my bony legs and my mud-spattered dress. I pulled up my sleeve and held out my arm. “For calling me by my name, not my number.”

“I wish we could have met somewhere else,” he said. “At the symphony, or a dance. If I’d walked up to you and asked you to dance —”

“I would have said yes.”

He weaved his fingers through mine.

“You’re shivering,” he said. “You need a warm drink.” I followed him downstairs to the kitchen. He made me a cup of black tea, dropped a cookie onto a plate, and slipped another into my pocket. The grandfather clock in the hall struck two.

Karl’s smile faded. “You should go.” He pulled off his scarf and draped it over my neck.

I hesitated.

“Go home, Hanna.”

“Home?”

Karl nodded. “You’ll be free soon. Go back to Debrecen. Find your family.”

“Come with me,” I said, surprised by my own daring.

“I can’t,” he said. “I’m the son of the commandant.” There was fear in his voice — sadness, too.

“I’ll tell them you saved my life. I’ll tell them . . .”

Karl shook his head.

“It’s not just that. If you go back to Debrecen and find your parents, how will you introduce me? They won’t understand, Hanna, and you can’t expect them to.”

“And if they’re not there?” My voice splintered.

“You’ll start a new life.” He took my hand. “You can’t do that if I’m with you, reminding you of your old one. Every time you look at me, you’ll be reminded of Birkenau.”

“Yes, and the music room at the villa.” I leaned in to him. “And our first kiss.”

I stood on my toes and brought my face close to Karl’s. I’d dreamed of our first kiss. I’d played the scene a thousand different ways, but never like this . . . standing at the front door, saying good-bye. Karl’s eyes dropped to my mouth. I could feel his heart pounding through his shirt, but he didn’t kiss me. He brushed my cheek with the back of his hand and then he reached up and pulled my scarf from my head. He ran his fingers over my stubbled head, traced the arc of my nose, the dark circles under my eyes. He looked at me, and it didn’t matter that my ears stuck out and my scalp glowed white. It didn’t matter that my dress was damp and my fingernails were dirty, and for a split second, I almost told him what I was thinking: I could love you.

And then he kissed me. Just the faintest brush of his lips against mine. It was like being thrown toward the sun. I waited for it to feel wrong, but it didn’t. I thought of the first time I’d sat down at a piano, how wonderful the keys felt under my fingers, how sure I’d been that nothing else would ever come close to the feeling I had sitting on that stool, making music.

We stood there, holding each other. Neither of us wanting to be the first to let go. I felt more alive, and afraid, than I ever had before.

And then a loud whistling sound tore through the room and the ground shook. Karl grabbed my sleeve and pulled me to the door.

“I don’t want you here when the Red Army turns up. Go back to camp, Hanna. You’ll be safe there. Please.” His breath was jagged. He reached for the door handle.

“Walk around the camp. Go to the bombed buildings hidden behind the trees. Go to the shower block on the other side of the tracks. Talk to people. Find out what we did.”

He pulled the door open.

“What your father did.” I buried my face in his neck. His skin was streaked with sweat, but I could still smell his musky scent. He stepped away from me and took my hands in his.

“Please,” he said, opening the door wide.

“You’ll leave, too?” I asked, searching his face. “Before they get here?”

He nodded and closed the door.