They reached an alcove and stopped.
“Shut off your headlamp,” Sam said, dousing his.
Remi did. When their eyes had adjusted to the darkness, they began to see slivers of dim sunlight through the foliage-covered walls and ceiling.
“Windows and skylights,” Remi said. “This must have been an amazing sight in its day.”
Sam and Remi started climbing a set of steps and soon reached a landing where the steps doubled back and rose to a second floor. Here, through an archway, they found a large open space. A patchwork of roots and vines arced above their heads to form a vaulted ceiling. Spanning the Great Room, as they dubbed it, were what looked like six half-rotted logs. Support beams, they decided, long ago decayed, the remnants held in place by a sheath of vines. Directly opposite the ramp/stairs they’d climbed was another set, leading upward into darkness.
Headlamps panning, Sam and Remi spread out to explore the space. Along the far wall Sam found a row of stone benches jutting from the wall, and, in front of these, six rectangular slots in the stone floor.
“Those are tubs,” Remi said.
“They look like graves.”
She knelt beside one and tapped the inside walls with her machete. She got back the familiar clang of steel on stone.
“Some more over here,” Sam said, crossing to the other side.
They found a semicircle of stone benches enclosing a round basin wider than Sam was tall. Remi repeated her routine but could not touch the bottom. Sam found a chunk of stone that had fallen off a nearby bench and dropped it into the basin.
They heard a muffled thump.
“About ten feet deep,” Sam said.
He crouched and shone his light down the shaft but could see nothing through the web of vines and roots. “Hello!” he called. There was no echo.
“Too much vegetation,” Remi guessed.
Sam found another rock and prepared to drop it.
“What are you doing?”
“Indulging my curiosity. We didn’t see any sign of this shaft on the floor below, which means it was behind a wall. It has to have a purpose.”
“Go ahead.”
Sam leaned over the shaft, angled his arm, then hurled the stone. Unseen, it thumped against the bottom, then again, then clattered against a hard surface.
Remi said. “Good call. It’s got to lead somewhere. Do you want to—”
Sam’s radio crackled to life. In between bursts of static, faint staccato voices came through the speaker. The snippets were hurried and overlapping.
“I think it’s Gupta and Ajay,” Remi said.
Sam pressed the Talk button. “Ajay, can you hear me? Ajay, come in!”
Static. Then Jack’s voice: “Sam . . . Gupta . . . has spotted a . . . is taking off.”
“He’s leaving,” Remi said.
They turned and ran down the stairs, Remi trailing with her slight limp. They crossed the den and headed down the tunnel.
Remi called, “What do you think he spotted?”
“Only one thing I can think of that would panic him,” Sam replied over his shoulder: “Helicopter.”
“I was afraid of that.”