When living a life of starbases, ships, and environmental suits, with all air refined and filtered between breaths, one thing a person quickly became unaccustomed to was dust, which was unfortunate because Cardassia 4 was likely the dustiest M-class planet in the sector.

As soon as the transporter released her, Eden started coughing, and Ral was not far behind. Once her throat was clear, Eden pulled her tricorder from her belt. “I’m showing a series of caverns a bit to the east, with signs of recent excavation. Something’s blocking my tricorder from seeing much past the entrance.”

“The baffling field is at least partially technological,” Ral said, watching her own transporter. “Though there’s also ore in the rocks hiding things. Explosive residue indicates low-grade Cardassian shaped charges.”

“Shaped charges…” Eden nodded, touching the heavy pouch at her side. The disc… the key. “I wonder.” She led the way toward the cavern entrances.

As they approached, she dropped behind a rock outcrop, tugging Ral down alongside her. “There.” A series of prefabricated structures stood around a central hole. “Pretty sure this is a dig site…”

Ral nodded, glancing down at her tricorder. “I’m not detecting life signs. Warmth, though… the structures are heated.”

“Come with me. Eyes open.” Eden moved into the camp, Ral moving beside her. I don’t see anyone. Tricorder still shows no life signs. And I don’t sense anyone…

“Maybe they’re down in the dig,” Ral suggested.

“Maybe,” Eden murmured. “Only one way to find out.” There was a rope descending into the hole, and Eden took hold of it, starting down. A moment later, Ral followed. They were engulfed in darkness quickly, and Eden paused a moment to activate the lamp on her belt. Anyone at the bottom of this hole will see us coming down.

But there was no one at the bottom – just a tunnel, which they started down. Cardassian light-poles lit the way, so Eden doused her lantern and kept going.

“Do you think we have the right place?”

Eden paused as the natural rock gave way to an arched, open gateway, a teardrop-circled flame at the peak of the arch. “We have the right place.

Ral gazed up at it. “Commander… it’s like the rock was guided to petrify the existing structure.” She checked the tricorder. “The stone is more than half a million years old. The metal within is blocking my tricorder.”

Eden nodded, checking her own, then blinked. “Ensign, step to the other side of the gate for a moment. Put the wall between us.”

“Aye.” Ral did as Eden said, and the moment she was out of sight, the sense of her – excitement, anticipation, curiosity, worry – winked out of Eden’s mind. When she returned, she looked at Eden curiously. “Commander?”

“It blocks my empathic abilities as well,” Eden said. “We’re going in blind.”

Ral shook her head. “We work on the Breen border, Commander. Aren’t we always going in blind?”

Eden laughed softly. “Your point is granted, Ensign.” She led the way along the path. “Hypotheses?”

“The more I look at the stone,” the Trill said as they passed a few small buildings and the chamber widened around them, “The more convinced I am that the petrificaiton was deliberately encouraged. The Tkon wanted this place to last, to be seen by the people who came after them.”

“Or their own descendants,” Eden said. “A lot of empires that stand for ages think they’ll stand forever.”

“The Tkon definitely lasted long enough to watch their own great works crumble to dust,” Ral said. “The question is, what was so important that they wanted to keep it in place forever?”

“Religious institution? Repository of knowledge?” Eden suggested.

“Place of extreme biological importance to them,” Ral said. “Like the symbiont pools on Trill.”

“There’s one other possibility coming to my mind,” Eden said. A hint of worry, excitement, anticipation.

“What’s that, Commander?” Ral let her longer stride keep her in pace with Eden’s quickening steps.

“A warning,” Eden said. “Like species all over the quadrant have found ways to preserve the warnings erected around nuclear fission waste.”

“The architecture here is late Tkon,” Ral said. “They wouldn’t have been producing waste products like that by this time.”

“Maybe they found something,” Eden murmured. Avarice. Hunger. Anticipation rising. “Something dangerous even they couldn’t destroy or neutralize.”

“If the Tkon couldn’t deal with it, can we?” Ral looked down at Eden, the worry in her sense showing in her dark eyes.

“We’re Starfleet,” Eden said. “The Tkon moved stars. We find their deepest secrets. In the end, we can do anything” Though sometimes at such cost…

They arrived at a large building, central to the entire area. The heavy stone-and-metal doors were gone, and she caught a scent through the open doorframe. “Ral… careful.”

They slipped in. The building was a single great open space, long benches filling it. Eden saw the first Cardassian researcher laid across the back of one of the pews, one foot dangling off the edge, a disruptor burn in her side. The second was in the aisle ahead, a third laying between two pews facedown.

She couldn’t tell much, without a closer inspection, but it was clear they’d been ambushed.

“Orion disruptor burns,” Ral murmured as she scanned the nearest corpse. “Pirates in the Cardassian system?”

“Orion disruptors are nearly as common on the black markets as Cardassian phasers,” Eden said. “These are researchers. They never had a chance…”

Ral frowned. “Is whoever did this still here?”

“I don’t think so,” Eden murmured. “But they might have come back. Stay alert.”

“Commander…” Ral pointed to a wall panel at the back of the room.

Rather than stone, the panel was uncovered metal, marked with symbols of circles and lines, a few words of Tkon text there. Eden made her way over. “Here at the center… a depression.” She pulled the disk from its pouch, placed it over the depression. A perfect fit. “This is what we’re looking for.”

While Eden packed the disk away again, Ral gazed at the metal wall. “These points are star systems. The Tkon didn’t mark systems by planets, but by how many and what kinds of stars, and their distance markers weren’t scaled.”

Eden nodded. “It’s in the form of the lines between the systems. I didn’t have time to get to the star classes in Tkon charts on our way here…”

“I did,” Ral said. “Trinary system here, one a neutron star. Giant orbiting a black hole…”

Eden listened to Ral go on. Almost time. Each system Ral described brought her closer to understanding.

“I can scan this into my tricorder,” Ral said. “Program in the Tkon star chart design…”

“No need,” Eden said quietly. “I know where we’re going.” Then she turned quickly, pulling her phaser rifle from her back as she did, and fired. The Nausicaan inching past the frame of the missing door fell, chest smoking from the heat of the blast, the only scream he had time for echoing through her mind.

“Commander?” Ral’s pistol was in her hand.

“Go,” Eden said, and they ran for the door.