“Hold up,” he said. The beam of his flashlight had caught a hairline fracture in the braids of lava. He let his light travel along its length, then pressed at it gingerly with one hand.

“Looks solid,” he said.

“Then let’s proceed,” Sully replied. “Carefully.”

“It’s amazing this tunnel hasn’t collapsed under the weight of the glacier,” said Chen.

They moved deeper into the cave, treading cautiously. When they spoke, it was in low tones, almost whispers.

“There’s a coating of ice beneath the snow here,” Sully said after a minute. “Spans the entire floor. Remarkably even.”

“And it’s getting deeper the farther we go,” replied Marshall. “At some point, this branch pipe must have been filled with water.”

“Well, it must have frozen with remarkable speed,” Sully said, “because-” But at that moment the climatologist’s feet slid out from under him and he fell heavily on the ice with a whinny of astonishment.

Marshall cringed, heart in mouth, waiting for the ceiling to come crashing down around them. But when nothing happened, and he saw Sully was uninjured, his alarm turned to bemusement. “You got that on film, right, Ang?”

The graduate student grinned through his sudden pallor. “Sure did.”

Sully rose laboriously to his feet, frowning and wiping snow from his knees. He had a cat’s ingrained displeasure of losing dignity. “This is a serious moment, Evan. Please remember that.”

They continued even more slowly now. It was intensely quiet, the only sound the crunch of their feet on the dusting of snow. The ancient lava walls to either side were dark. Sully led the way gingerly, brushing the snow away with his boots, passing his flashlight beam back and forth over the path ahead.

Chen peered into the gloom ahead. “Looks like the cave opens up ahead.”

“That’s good,” Sully replied, “because the ice sheet’s getting deeper, and-”

Suddenly he fell again. But this was no clumsy repetition: Marshall immediately grasped that this time the scientist had fallen out of sheer surprise. Sully was frantically wiping away the snow underfoot and probing his light into the ice beneath. Chen dropped to his knees beside him, the camera temporarily forgotten. Marshall came quickly forward, peering down into the ice.

With a chill unrelated to the cave’s air, Marshall saw what Sully had found. There, buried beneath the ice floor, two fist-sized eyes-yellow, with black oval pupils-were staring implacably back up at him.

The trip down the mountain was as silent as the journey up had been chatty. Marshall could guess what they were all thinking. This discovery would change what up to now had been a quiet, unglamorous, even monotonous scientific expedition. Exactly how things would change, none of the scientists could say. But from now on, everything would be different.

At the same time, he knew, everyone was privately asking one question: What the hell was it?

Sully broke the silence. “We should have taken an ice core for testing.”

“How long has it been there, do you think?” Chen asked.

“The Fear’s an MIS-2 glacier,” Marshall replied. “That cave has been buried at least twelve thousand years. Maybe much longer.”

Silence settled over them again. The sun had finally succeeded in burning through the low-hanging clouds, and as it sank toward the horizon it ignited the snowpack into fiery brilliance. Absently, Marshall pulled a pair of sun goggles from his pocket and snugged them into place. He was thinking of the unfathomable blackness of those dead eyes under the ice.

“What time is it in New York?” Sully asked at last.

“Half past eight,” said Faraday.

“They’ll have gone home; we’ll try first thing in the morning. Ang, will you make sure the satphone is fired up before breakfast?”

“Sure thing, but I’ll need to apply to Gonzalez for fresh batteries, because-”

Chen stopped in mid-sentence. Looking up, Marshall immediately saw what made the graduate student fall silent.

The base lay a few hundred yards below, the long, low structure rusted and sullen-looking in the dying sun. They had followed the glacial valley in a gentle curve, and the main entrance to the base was now in view beyond the security fencing. Penny Barbour, the team’s computer scientist, stood on the concrete apron between the guardhouse and the central doors, wearing jeans and a plaid flannel shirt. The air was very still, and her short, mouse-brown hair hung limply over her forehead. Beside her was Paul Gonzalez, the sergeant in charge of the tiny posting that kept Fear Base nominally operational.

Four figures in heavy parkas, trousers of polar bear fur, and animal-skin mukluks surrounded them. One was holding a rifle; the others had spears or bows lashed to their backs. Although their faces were hidden, Marshall was certain these were Native Americans from the small encampment to the north.

As they quickened their steps toward the base, Marshall wasn’t sure whether to feel curiosity or alarm. Although they’d been on-site for a month, the scientists had had no interaction with the Indians. In fact, they only knew of their existence because the soldiers at the base had mentioned it in passing. Why would they choose today, of all days, to pay a visit?

As they passed the fence and empty guardhouse and approached the entrance, the group turned to face them. “This lot knocked on the door not two minutes ago,” Barbour said in her broad North London accent. “The sergeant and I came out to meet them.” Her plain, friendly face was pinched and somewhat worried-looking.

Sully glanced at Gonzalez. “Has this ever happened before?”

Gonzalez was fifty-something and burly, with the clear-eyed fatalism of the career soldier. “Nope.” He unshipped his radio to alert the other soldiers, but Sully shook his head.

“That won’t be necessary, will it?” Then Sully turned to Barbour. “You’d better get back into the warmth.” He watched her head for the main entrance, then cleared his throat, faced their guests. “Would you like to step inside?” he said, slowly enunciating each word and gesturing toward the door.

The Native Americans said nothing. There were three women and a man, Marshall noticed, and the man was by far the oldest. His face was seamed to an almost leathery complexion by years of cold and sunlight. His eyes were a clear, deep brown. He wore large earrings of bone, carved with fantastic detail; there were feathers in the fur of his collar; and his cheekbones bore the dark tattoos of a shaman. Gonzalez had told them the band lived a life of unusual simplicity, but- Marshall thought, staring at the spears and animal skins-he’d had no idea just how simple.

For a moment, an uncomfortable silence settled over the group, the only noise the grumbling of the nearby generators. Then Sully spoke again. “You’ve come from the settlement to the north? That’s a long journey, and you must be tired. Can we do anything for you? Would you like something to drink or eat?”

No answer.

Sully repeated himself, slowly and emphatically, as if speaking to a half-wit. “You like drink? Eat?”

When there was no response, Sully turned away with a sigh. “We’re not getting anywhere.”

“They probably don’t understand a word you’re saying,” said Gonzalez.

Sully nodded. “And I don’t speak Inuit.”

“Tunit,” the old man said.

Sully turned back quickly. “I’m sorry?”

“Not Inuit. Tunit.”

“I’m very sorry. I’ve never heard of the Tunits before.” Sully patted his chest lightly. “My name is Sully.” He introduced Gonzalez and the scientists by name. “The woman you met is Penny Barbour.”

The old man touched his own breast. “Usuguk.” He pronounced it Oos-oo-gook. He didn’t offer to introduce the women.

“Pleased to meet you,” Sully said, as usual playing his role as team leader to the hilt. “Would you care to step inside?”