Fred wanted to stare at the gold symbols and the light they cast, but something warned him that this would be dangerous.
He had long ago learned to listen to that inner voice when on pa- trol or in the heat of battle. It had saved him from dozens of am- bushes. He kept his eyes on the dirt floor of the tunnel. There was something too fascinating and nearly familiar about those symbols. They reminded him of the Greek mythology that Deja, the Spartans' first teacher, had taught—legends of hauntingly beau- tiful creatures who lured the unwary to certain death. Sirens.
He checked his rifle. The ammo counter read full, but he hit the magazine release and visually confirmed it. He slapped the clip back into the receiver. This simple operation cleared his head.
He detected four blips on his motion tracker—they glowed green, indicating fhendlies.
Kelly, Vinh, Isaac, and Will jogged up next to him, weapons ready.
"What is this?" Will whispered. The golden glow reflected in his helmet's faceplate.
"Careful," Fred warned them. "Filter the light. Go to black-and-white image enhancement."
He got four blue acknowledgment signals, and then Fred switched to BWIM display. Funny that he hadn't thought of that for himself. Only when the safety of his team was at stake did he think clearly.
Dr. Halsey ran along the tunnel and halted, panting, next to the Spartans. "Yes," she said, wheezing. "Yes, this must be it—what Ackerson was searching for. And most likely"—she glanced at the roof—"what they are looking for, too, I imagine."
Dr. Halsey ignored the curious symbols and the light, and strode into the new corridor. "Hurry," she told them. "I fear we've set something in motion, and our visitors upstairs might know it, too."
Fred assembled his team to form up around Dr. Halsey. Kelly took point, and the rest of them created a loose box around her.
Dr. Halsey handed Fred his missing gauntlet. He took it and wriggled his fingers into the armor, pulled it snug, and sealed the locking collar around his wrist. Diagnostics ran and confirmed that his armor was whole again. His motion tracker pulsed on his heads-up display.
The hallway changed as they continued down its length. The golden light faded along the ceiling, and inky black covered its expanse; tiny stars winked on and twinkled. Fred added color to his display; he wanted to see this. Moons wheeled overhead; silver-gray orbs, pockmarked with meteorite impacts, spun in wide orbits. Along the walls, tall green bamboo-like grass sprouted and grew up the curved surfaces.
Dr. Halsey brushed her fingertips along the wall, and the grasses wavered at her touch. "Semisolid holography," she said without halting. "No visible emitters. Interesting. We should investigate this later," she said and increased the pace of her stride.
"If there's time."
The holographic environment cycled to an arid moonscape: deep craters and sterile light; it became a volcanic world with lava flowing alongside them. The air wavered with heat. In each transformation the golden symbols remained on the walls, lead- ing them through the illusions.
The corridor emptied onto a landing that overlooked the largest room Fred had ever seen.
Kelly stepped onto the landing, looked, and waved them forward.
They stood on one of a dozen tiered levels that encircled the room; there was no railing. Fred leaned over the edge. It was at least one hundred meters to the floor below. The room was ap- proximately circular and three kilometers in diameter. The floor was blue and seemed to shift as a billion tiny tiles flexed and re- arranged themselves into frustratingly familiar patterns. The ceiling was a dome with a holographic golden sun, blue sky, and cottony clouds that morphed into spheres, puffy pyramids, bars, and cubes. And in the center of the floor was a pedestal flickering with a faint light.
Isaac held up his hand. "Listen," he whispered over the COM.
They all froze, and Fred strained to hear. There was nothing.
Fred turned up his aural amplification to maximum gain. He heard the creak of their armored joints and five faint heartbeats but, other than that, silence.
"They've stopped," Fred said, and pointed overhead. "The digging."
"I don't like it," Dr. Halsey said. "The Covenant aren't known for giving up on anything they start. We'd better continue."
Kelly removed the clip from her magnum, cleared the cham- ber, and then slid a self-installing piton down the length of the barrel. She shot it into the stone wall, and the metal shard im- planted ten centimeters and blossomed with sharp talons, secur- ing the shaft to the wall.
Vinh handed her a coil of black rope. She clipped one end to the piton, then tossed the rest over the edge.
Isaac and Will stood on the lip and swept the vast open region with their weapons.
Kelly jumped and rappelled to the bottom. A moment later she gave the all-clear signal.
Will and Isaac followed her to the floor. Fred tied the rope around Dr. Halsey's waist and lowered her gingerly down after them. He and Vinh took up the rear.
The floor of the great room wasn't the same tile as in the cor- ridor above. It was still blue tile, but these were squares and circles and bars and triangles. If the symbols were a language, Fred stood upon a million words; he wished he'd been issued a dictionary.
Dr. Halsey paused to examine the tiles as well. "If only we had the time," she muttered, and then walked toward the light gleam-ing in the center of the chamber.
The Spartans formed up around the doctor again, but Fred's instincts warned him that this wasn't a good idea. He couldn't get his bearings straight. The room was big, large enough that it felt as if they were outside. It threw him off. He had an odd sense of vertigo, almost as if the floor was tilting and he was now walking on the roof.
Dr. Halsey increased her pace, but the distance to the center of the room didn't seem any closer; in fact, they seemed more dis- tant from the center than when they had started out from the edge of the room.
Fred turned down the gain on his display until everything was a faint black-and-white blur. He focused on his motion tracker and saw that the Spartans and Dr. Halsey were now separated across two dozen meters.
"Everyone stop," he said. "Regroup. We're getting scattered."
They halted and edged back into formation.
"There must be another way," Dr. Halsey said. She reached into her lab coat pocket and removed a ball bearing. "The floor slopes toward the center," she observed. She set the bearing on the floor and gave it a gentle push. The bearing rolled, then curved, and spiraled back to a stop.
"This is getting too weird," Fred muttered. "Kelly, you have the best aim. Close your eyes, pick a direction, and we'll follow."
"... Affirmative," she whispered.
The Spartans set their hands on each other's shoulders and marched, not toward the center of the room but to a spot that Kelly picked, apparently back the way they had come.
Fred turned off his display and watched his motion tracker.
They were all together and another blip appeared, one that Kelly was leading them straight to.
Another twenty meters and she halted. "Look."
Fred snapped on his heads-up display, and sapphire-blue light filled his vision. They stood before the source of the glow in the middle of the room. There was a pedestal made of the same gold material as the symbols in the corridor, and floating above it was a fist-sized crystal, tapered to a point at either end. It spun, and the facets along its centerline folded and shifted like the pieces of a puzzle.
Dr. Halsey reached for it and then hesitated. "Radiation?" she asked.
Fred checked his counter. "Normal background levels," he reported.
"We must take this with us," she whispered. "Study it. Or destroy it if necessary to keep the Covenant from getting it." She touched the crystal, and its light dimmed. For a moment the light appeared to be absorbed by Dr. Halsey's palm.
Static washed over Fred's display, his shields shimmered, a squeal blasted through his speakers, and his motion tracker mo- mentarily made contact with a thousand targets swarming through the great room. His radiation warning flared red and then faded.
"Radiation spike," he said. "Analysis says lots of neutrinos, but I'm unable to determine the type—it's something not in the computer's database."