Inside, she bought two colas, stood in the weak shadow of the overhang, and chugged the first one. She noticed a sparrow fluffing its feathers under a picnic table, beak open, panting. Even the lizards moved in short, frantic bursts between slivers of shade.

Lena leaned forward. A single crack, thin as a spider’s thread, had appeared just above the rearview mirror. It didn’t spread from an edge. It started in the middle, an ugly little star with a black center where the glass had actually fractured.

“No way,” she whispered.

Lena turned off the AC and rolled down the windows. The heat rushed back in, but the damage was done. She’d have to drive the last two hundred miles squinting through a web of fractures, counting herself lucky the whole thing hadn’t exploded in her face.

The glass hadn’t failed because it was weak. It failed because heat and cold, when they meet too quickly, forget how to be friends. And in that forgetting, something has to break.