“I’ll stay here,” said Nina. “You guys can send for help.”

Marcus shook his head. “This place doesn’t work that way.”

Lou listened as the others slipped and slid down the slope. No one was screaming or whimpering or making any noise at all. Was this a good sign, or bad? “Come on,” she said to Nina. “Marcus will go ahead of you. And I’ll go behind. You’ll be safe between us.”

“But what is that stuff?” Nina asked, gesturing to the black rot that was coating the walls.

“Don’t think about it,” said Marcus, taking her hand. To Lou’s surprise, Nina stepped through the doorway.

Lou followed. She tried to not touch the walls, but the floor was so slippery, she had to reach to remain upright. She pressed her hands into the cold slime until her palms met a solid surface several inches underneath. She kept the back of her throat closed and forced herself to think of the wildflowers that grew on Mount Diablo, of her mother’s sweet perfume that she wore to temple, of the crisp scent of the balsa wood she’d used to make dollhouse furniture.

The space inside the refrigerator was slim—only about two and a half feet wide and maybe four feet tall. The slope descended much more steeply than Lou had anticipated. Nina walked slowly before her, sliding and skidding to a stop with nearly every step. Marcus called out to them from up ahead. “You two okay back there?”

“So far so good,” said Lou. But Nina only murmured, “Mmmm.” Was that a yes or no? Lou wondered. They’d made it a few yards and had about a dozen to go.

Wham!

The tunnel trembled.

Glancing over her shoulder, Lou discovered the refrigerator door had slammed shut. The sound of squealing metal and crunching ceramic blasted from the darkness. It took a moment for Lou to understand what she was seeing: the tunnel was collapsing behind them, squeezing in on itself, as if someone were clenching it like a tube of toothpaste.

Ahead, Nina was frozen with terror. She pushed at the sides of the tunnel as if trying to keep herself in place. “Go forward!” Lou yelled. “Hurry!”

But Nina only answered with “No, no, no, no, no …”

Crunch!

The top of the tunnel dipped several inches. Lou dropped to a crouch.

Crunch!

She looked back again. It was dark, but Lou could tell that the collapse was coming closer—too close for comfort. “You have to move, Nina, or we are both going to be crushed.”

Nina released a tight-lipped wail, but she didn’t budge.

Crunch!

Now Lou could feel pressure by her toes. There was no room to adjust her feet. If the tunnel flattened any farther forward …