The scream came again, accompanied by the sound of splintering wood as the baboon attacked one of the crates—all of which were in the Cloud Chamber, next door to this room.

Sam looked around. It took almost no thought to grasp the trouble they were in. There was no door they could shut to close this third room, and no place within the room to shelter them. No place to even hide. The room was bare except for Mr. Coleman’s body.

The big entry room outside was no better: it had the counter along the back wall, but no cabinets beneath it. Just empty space.

The Cloud Chamber had a door—but the baboon was already in there.

Could the two of them run to that door right now and throw it shut, trapping the animal inside the chamber?

Sam pictured them trying it—trying to swing that heavy, two-inch slab of glass closed before the baboon saw them and lunged at them.

He shook his head; it wasn’t even worth thinking about.

That left one more room to consider: the little one with the card table and the wrecked computer. Useless.

Sam stepped to the doorway. Dani moved with him. They could hear the animal still ransacking the crates inside the Cloud Chamber. They stared across the larger room at the steel door leading back to the ladder shaft. The thirty-foot distance to it looked more like a hundred yards. Even if they could reach it, get through and slam it shut from the other side, there was no way to latch it. All the locks had been drilled out. They’d just have to stand there holding it shut against the force of an enraged, hundred-pound animal on the other side.

Another wild scream. Another crash of breaking wood.

How long before it lumbered into this room? A minute? Even that much time felt like wishful thinking.

“What the hell do we do?” Dani whispered.

Sam didn’t answer. He didn’t know.

He stared at the distant door, the ladder just visible in the orange-lit chamber beyond. Running for it could get them killed, but it was all he could do to keep from trying it anyway. Just grabbing Dani and propelling her forward as fast as they both could go.

Instead he swept his eyes across the rest of the big room—and saw what they had to do.

The only thing they could do.

He whispered it to Dani. She looked at him like he was crazy. Then the baboon shrieked again, and she nodded, fast and frantic.

They each took a deep breath—and ran.

Not for the door to the shaft.

For the open cage.

The instant they left the smaller room, Sam felt like he was in the nightmare where your limbs seemed to weigh a thousand pounds each, and you could barely run, while the monster had no such difficulties.