The assault went on for twenty or thirty seconds. Then the baboon drew back from the cage, its deep-set eyes glaring but losing their aggression. It lumbered forward and gave the door one last bash, and then it loped over to the room with the card table and set to work demolishing it further.

They waited. Ten minutes passed. The baboon tore apart what remained of the computer that sat on the card table, then focused its rage on the table itself, pounding it and tearing at the plastic surface with its claws. After a while the animal lost interest. It staggered back into the large entry room. It looked weary. It looked sick. The blood was running in streams now from its nose and eyes. Its shoulders spasmed and jerked.

“What the hell did they do to it?” Dani whispered.

“Rigel,” Sam said. “Whatever Rigel is, that’s what they did to it.”

“Some kind of drug, you think?”

“I don’t know,” Sam said. It seemed possible. Lots of things seemed possible.

One thing was certain: whatever work these people had been doing here, to re-create Rigel, they had finished it. Now they were out there somewhere, with their results in hand.

The baboon collapsed again a few minutes later. It sank to the floor in the middle of the entry room, ten feet from the cage Sam and Dani were holed up in. It rested its head on one arm and shut its eyes, and its breathing softened until they could no longer hear it.

They waited another five minutes. The thing didn’t move. They looked at each other and nodded, and Sam eased forward to get a look at the jammed door of the cage. He could see easily enough what it would take to open it: contorting the cage itself, by pushing against one corner or another, to take the pressure off the spot where the door was wedged.

He worked at it slowly—quietly. He kept his eyes on the baboon as he did. A minute later the door slipped free of the frame.

The climb up the ladder shaft seemed to take forever. They both stared down the entire time, watching the orange light shrink away below them, and hoping like hell they didn’t see a shape suddenly block it out.

They reached the top, clambered out of the pit and hurried into the room beyond—the short corridor with the grey ceramic tiles and the stenciled writing on the wall. They crossed to the far end and pulled open the steel door that led out to the staircase, and slammed it shut behind them.

Dani took a step back and lost her strength. She sat down hard on one of the concrete stair treads and put her head in her hands.