But I could not lie to her again. “Krys was arrested,” I told her at last. “Taken. He went to try to intercept the munitions and he was caught.”

A horrified look crossed her face. “Arrested?” I expected her to panic. “Oh, Ella, you must be so worried.” Her voice was laced with concern. “You have to go to him, to help.”

“There’s nothing I can do for him now,” I said, willing my voice not to crack. My stomach twisted anew at the thought of Krys, arrested or worse. In that moment, I would have done anything to help him. But as Kara had said, that was not what Krys would have wanted. My place was here, rescuing Sadie. “This is what he would have wanted me to do.” I hated how I spoke of him in the past tense instinctively, as if he were already gone.

“But without him, how can we possibly escape?” Her doubts seemed to double anew.

“I know the route,” I said, which was partially true. “Kara, the woman from the café, told it to me and said she’d help. I can get us to safety.” I tried to force confidence into my voice. I just had to get Sadie and the others out of the tunnel on my own and then Kara would help them reach Kryspinów. I could do this. “Come.”

We walked through the tunnel in silence. I led the way, with Sadie right behind me. “I’m so sorry about your mother,” I said. It was perhaps unwise to bring up the subject again and upset her just as we were leaving. But I felt that I needed to say something.

She sniffed. “There was some part of me, I think, that already knew when she hadn’t returned after so long.”

Behind her, Saul helped his father, who moved slowly. Convincing them to leave had taken longer than I had anticipated and I wanted to urge them all to hurry. The old man had been crippled by the months in the sewer, though, and could barely walk. I concentrated on the path ahead, trying not to think about the mines. I had no idea what they looked like or how we might avoid them and it seemed that every step might be our last.

We made our way toward the grate where I had first met Sadie, the one near the Dębniki market. I didn’t know how we would all get out, or avoid being seen, even at night. I prayed Kara would be there to help us. One step in front of the other, I heard my brother Maciej’s voice say, as he used to during tough times. That is all you can do.

Suddenly there came a rumbling sound. At first I thought it might be an air raid, but it was too close and intense. The walls began to shake. Sadie stumbled and I could not reach her, but Saul grabbed her before she could fall.

One of the mines had detonated.