“The where I can answer,” Koval said indolently. “The why is none of your business.”

It was no easy feat to land a space vessel unnoticed near a populated area on a planet where the sound of an engine had never been heard before. It would be one thing if they were an anthropology team simply studying the inhabitants; they might have set Albatrossdown anywhere in the hinter-lands and hitchhiked into town in the back of an oxcart. But in this instance they needed speed as much as stealth. The ship had to be close to their objective.

“I’d be happier if this were a shuttlecraft with a starship for backup,” Sisko muttered, searching the terrain near where they’d picked up the Rigelian’s signal for a safe place to conceal the ship. He was reluctant to leave her in orbit at station-keeping and beam down, but this time thought he’d ask Tuvok for his input before he made his decision.

“I figure there’s too much likelihood that we’d be noticed beaming out. More to the point, I don’t like leaving her alone up there in case someone should get curious.”

“Agreed,” Tuvok had said. “However, landing the ship will necessitate our splitting up into shifts again.”

“Logically, Lieutenant Sisko,” Selar suggested, “as the two best trained for alien terrain conditions, you and Lieutenant Tuvok are the optimal choice for first reconnaissance. Further, I am in the middle of an experiment which requires my complete attention. Zetha can remain with me.”

It was what Sisko had had in mind. Now all he said was: “You’ll keep her sealed up until we signal you.”

“Of course,” Selar said, turning her attention back to her scanners.

Albatrosswaited until sundown before gliding into atmosphere on thrusters and, in a daring maneuver he’d never tried anywhere but in simulations before, Sisko cut the engines entirely for the last hundred meters and let her momentum carry her until he swore he could count the blades of saw grass skimming by beneath her belly. Just when it looked as if he could reach out and grab a handful of that grass, he activated the reverse thrusters in a series of short bursts which, if all went well, would neither scorch the grass nor awaken the neighbor’s dog, and Albatross,once more true to her name, bumped awkwardly but unhurt to ground. Only the sheen of sweat on Sisko’s brow revealed just how uncertain he had been that she would.

Selar and Zetha were holding things down back in the lab, oblivious to how dangerous the maneuver had been. Tuvok, still hoping to pick up more signals from the two Romulan transmitters, was also monitoring the Rigelian’s underground lair, and had barely noticed the descent.

“The cave is deserted at present,” he announced once he and Sisko had left the ship, scanning once more with his tricorder as they prepared to go exploring. “Doubtless its owner has returned to hearth and home.”

“Let’s hope it’s for the rest of the night. Don’t suppose a longbow is any use inside a cave?” Sisko mused, absently groping at his hip where a phaser ought to be. “Oh, well. There are two of us. How strong can one Rigelian be?”

The cave was indeed deserted, but if the two Starfleet officers expected to find a laboratory, however primitive, they were disappointed. What they found was a dirt-walled cavern only partially excavated from a natural formation, dimly lit by a few overhead lamps. Several rustic tables against the walls of this crudely formed room were cluttered with jars of various sizes and colors, obviously made by local craftsmen, as well as the transmitter which had led them here, which was indeed of Romulan design. There was also a computer terminal which seemed to have been cobbled together from modules salvaged from a vessel augmented with Romulan components.

“Hybridized Rigelian computer,” Sisko announced, just looking at it. “That particular style of interface is something they use.”

There was a refrigeration unit, also of Rigelian manufacture. Instead of specimens or test samples, the refrigerator was cluttered with containers of half-eaten food, much of it spoiled.

“Likely solar powered,” Sisko said, indicating the generator. “Might be able to find the collectors out there in the daytime.”

While he searched the fridge for anything resembling research samples and ending up with nothing more than moldy stew, Tuvok attempted to gain entry to the computer, something which proved not at all difficult. There were some rags and what looked like parts scavenged from a ship piled against one wall, covered in dust and cobwebs, and Sisko began picking through these as well.

“Clothing’s synthetic,” Sisko reported. “Modern stuff, not something you’d find woven on a handloom in a preindustrial society. Food looks local, though.” He heard the Vulcan’s indrawn breath at something on the computer screen. “What is it?”

“Pornography,” Tuvok said, repressing his distaste. “There seems to be nothing on the computer but that. I find no records, no experimental data—”

“Nothing but dirty pictures, huh? Maybe he’s got the data stored somewhere more portable. This is a hideout,” Sisko decided. “The kind of place a man goes to when the wife and kids get on his nerves.”

“Indeed. Perhaps Cinchona’s laboratory is elsewhere.”

“I’d be surprised if he had a laboratory at all.” Sisko picked up a few of the jars, opening the lids and alternately peering inside or sniffing at them. “Hilopon?It looks like dirt.”

Tuvok ran the tricorder over the jars. “Hilopon.As Selar suggested, a natural compound found in the soil of Renaga, just as the original Gnawing bacillus was found in the soil of Romulus.”

So saying, he ran the tricorder over the walls and the dirt floor of the cave and came up with the same readings. “The substances in the jars may have been refined to remove gravel and other debris, but it is essentially no different than the soil beneath our feet. Curious.”

“Or just plain dumb.” On a hunch, Sisko rubbed the contents of one of the jars on a small cut on one finger he’d acquired while chopping the last of the Vidalia onions he’d purchased on Tenjin. The cut healed instantaneously. “Cinchona was right about one thing. It does work for small stuff, at least on its own planet.”

“Cinchona was right about more than that,” a voice said behind them.

Selar motioned Zetha to join her in peering at the specimen under the microscope. The girl’s eyes widened in astonishment.

“Is it the hilopon?”she wondered.

“Negative,” Selar replied. “After our departure from Quirinus, I derived a serum from the blood of the Romulan who was killed because the Quirinians believed he had brought the disease.”

“The one who had no…germs,” she pronounced the word carefully. “…in his body at all.”

“Correct. I treated several of the Catalyst mutations with the serum. These are the results.”

Zetha examined them again, just to make sure she understood. Before she could speak, Tuvok’s voice on the intercom interrupted.

“Dr. Selar? Can you beam into the cave at once? Your expertise is required.”

Selar brought Zetha with her. It seemed the logical thing to do. Besides—

“Please don’t leave me here by myself,” Zetha pleaded. “If anything goes wrong, I won’t know what to do.”

“Dubious,” Selar said. “You have managed quite well so far. However, for Lieutenant Sisko’s peace of mind as well as your own safety, it might be best if you did accompany me.”

“Did my father send you?” was the first thing Thamnos asked his two unexpected visitors. Then something seemed to tell him that was not the appropriate question, so he asked another. “How did you find me?”

“Is that of consequence, Dr. Cinchona?” Tuvok asked, suppressing any sign that he knew who Thamnos was; Sisko had suggested he do most of the talking when they first confronted their suspect. “I am Tuvok. This is Dr. Jacobs. We have read your paper on hilopon.We wish to learn more.”