By afternoon the building felt like a mouth.

Jude had two bottles of warm water left and a bag of ice that was already a bag of water. Lena put on last night’s tank top and his shorts, rolled twice at the waist. No underwear. The seam sat against her in a way she felt on every step.

“Store on the corner had a generator last night,” he said. “Might still.”

They took the stairs. Four floors. The stairwell was the coldest place left, which was not saying much. Concrete. A strip of light from a high window. Somebody’s takeout bag rotting on a landing.

They made it to the...