He raised a finger to his lips, and pointed upward. They were on the same section of the stairs. Madeleine nodded slightly, as if vigorous movement might give them away.

They walked in silence from then on: not quite, though, for while Madeleine’s feet made no noise on the cold steps, Petrovitch’s boots did, no matter how carefully he placed them. He contemplated taking them off and slinging them around his neck, but going barefoot to his death was too much for him to consider. Better to die with his boots on.

At floor fifteen, they heard more doors closing. Whoever was with Sonja wasn’t being careful, and that was a good sign: they weren’t expecting company. Petrovitch raised an eyebrow heavenwards, and Madeleine leaned in close to his good ear.

“We’re gaining on them.”

Petrovitch put his hand on his sternum, checking that his heart was still beating. That he hadn’t felt any erratic behavior from it for a while worried him, because he paced life by its various twinges and aches, and let his defibrillator punctuate him when it needed to.

He could be killing himself by climbing at such speed.

The doors below them peeled open and snapped shut. Hoarse coughing rattled the air, going on and on until it ended in a ghastly retch.

“There’s someone else coming,” mouthed Petrovitch.

“Really?” mimed Madeleine back. She pointed to him, then up the stairs. “You, go.”

He frowned.

She tapped herself and held up the pipe.

Petrovitch shook his head.

She pressed her mouth to his ear. “Now is not the time to argue. I’m here to make sure you get to where you’re going. I’ll see to whoever it is coming up the stairs, and then I’ll join you. It’s not like you’re going to make it to floor fifty before I catch up to you, is it?”

He tried to pull back, but she wrapped her arm around his neck and held him still.

“If you take some stupid stray shot meant for me, I won’t know what to do with the Jihad. You’re the one who’s going to stop it. Not me. So I have to protect you, and you have to accept that. Okay?” She kissed the side of his head and pushed him away, flapping her arms like she was chasing a pigeon.

He watched her descend, creeping along, back hard against the inside curve of the spiral stairs. Then she was gone. He couldn’t hear her at all, just the coughing and hawking of phlegm from five floors below.

He turned around and forced his legs to move. Thirty-four more floors.

35