IT TOOK ALL Maddy’s strength to hold back a shout. She fought every instinct to run forward and wrap her grandmother up in her invisible arms, guard or no guard. Instead, Maddy silently followed him into Cell 13 and pressed herself up against the front bars.

Jessica’s yellow prison jumpsuit practically swallowed her small body. Her silver hair was pulled back into a tight bun. She stepped to the middle of the cell as the guard grabbed her mattress—nothing more than a thin pad—and tossed it onto the floor. He used his rifle butt to test the window bars and tapped at a few chipped cinder blocks in the middle of the wall.

“You caught me,” said Jessica. “I was chewing my way out.” The guard ignored her sass and turned toward the door.

“Replace your bedding,” he said as he stepped back into the cell corridor.

“Close Number Thirteen!” he shouted.

The door clanged shut.

“Open Number Fourteen!” yelled the guard, moving on to the next prisoner, the woman in the red turban. For some reason, she had been allowed to keep her headwear. It created a bold contrast with the mustard color of her prison uniform. She stood holding her mattress in her hands, shaking it vigorously.

“Thought I’d save you some time,” she said.

“Drop it!” said the guard. He was in no mood for attitude. Besides, he’d been warned that a mattress could conceal a length of wire or a sharpened shard of stone.

Suddenly, a scream came from the previous cell. Number 13.

“Help!” the woman was shouting at the top of her lungs. “There’s something in here!”

Rat! was the guard’s first thought. They usually stayed hidden until dark, but sometimes the inspections stirred one from the nest. He pulled a short club from his belt. A rat wasn’t worth a bullet or the risk of a ricochet. One solid whack would take care of it.

He moved back to Cell 13. The old woman was sitting on the metal bed. But something else was happening. Something very strange. Her mattress was floating in midair—waving and rippling like a magic carpet.

“What the hell?” said the guard. He shoved the club back into his belt loop and turned toward the control room.

“Open Number Thirteen!” he shouted.

The cell door began to clatter. When the guard looked back into the cell, the mattress was lying still on the floor. But now, he saw two people in the cell. The old lady in the jumpsuit. And a teenage girl in shorts and a T-shirt. The guard flipped his rifle into firing position.

“Who the hell are you?” the guard asked Maddy. “How did you get in here?”

“Is there a policy against guests?” asked Jessica.

The guard was young and new to prison duty. A veteran would have called a code eight immediately, bringing a riot team to the scene in seconds. But this kid was green enough to think that he could resolve the problem on his own. It was an old lady and a girl his age, after all. No big deal.

Then the girl said, “Step into the cell and take off your clothes.”