“Dismissed,” Vaughn said with a paternal smile, then watched as Nog exited.

He looked toward Bowers, who occupied the tactical console. “Please open a channel to the D’Naali ship, Mr. Bowers.”

“Aye, Captain,” Bowers said.

Moments later, a bug-visaged alien face appeared on the screen, its vertical mouth parts spread in what might have been a D’Naali smile. “Grateful thanks of ours you have, humandefiantcaptain. Indebtedness, with thanks/ beholden again reiterated/multiplied.”

“Not at all. We were happy to assist you.”

“Anything in recompense/requital, we offer with gladness/joy to provide/make available. State the need/ request.”

Vaughn blinked while he parsed the translator’s fractured grammar. Then he realized that the D’Naali commander was not only presenting his thanks, he was offering to provide something of value in return for the Defiantcrew’s labors.

He decided to seize the opportunity. “There is one thing we’d like to ask of you.”

“Denominate that one thing, I request.”

“We need to survey a remote part of this solar system. In the outer comet cloud. We could use a guide who is familiar with the territory.”

The D’Naali lapsed into what seemed a thoughtful silence before he spoke again. “Answer/result is affirmative/positive. Ryek’ekbalabiozan’voslu now dwells aboard your vessel.”

Vaughn realized that the other captain was referring to the D’Naali whom Bowers had dubbed Sacagawea.

“We would be grateful if Sacagawea would act as our guide,” he said, glancing back toward Bowers, who now looked somewhat embarrassed. Vaughn was aware, of course, that the translators had been calibrated to render the nickname into the D’Naali language. “If he is willing.”

The D’Naali captain made a sweeping gesture with one of its slender limbs. “Unneeded it is to check. Ryek’ekbalabiozan’voslu will be/is obligated to be your guide. What time-interval is requested/required?”

“A few solar days at the most,” Vaughn said. “Then we will return your crew member to you.”

The D’Naali captain’s head bobbed up and down. “Assent granted readily/with enthusiasm. After/following five turnings-of-the-star, we will await/expect your return to this place/coordinates.”And with that, he vanished, replaced by an exterior view of the D’Naali ship.

Vaughn returned to the captain’s chair, sat, and looked at the conn station, where Tenmei was posted. Her dark eyes regarded him expectantly, and he could see that she had already laid in a course.

“Best speed to the alien artifact,” Vaughn said.

The flight into the fringes of the system’s Oort cloud, guided by the subspace beacon Nog had deployed during the Sagan’s close encounter, took less than ten minutes. Vaughn ordered Tenmei to bring the Defiantto a relative stop a mere one hundred kilometers from the coordinates where the Saganhad nearly been swept forever out of normal space by the enigmatic artifact’s interdimensional effects.

In the center of the screen, an indistinct structure appeared, growing steadily in apparent size as Tenmei increased the viewer’s magnification levels. At first, Vaughn thought it might be one of the countless dead, icy bodies that spangled this cold, remote region of the system. These objects were diffused throughout the Oort cloud, covering a volume of space so vast and dimly illuminated by this system’s distant sun that any one icy body was scarcely distinguishable from any other.

But the object that was growing on the screen swiftly resolved itself into something else entirely. Its artificial nature was now clearly discernible, as it continued its stately, eternal tumble through the unfathomable interdimensional deeps. Its shape was constantly morphing as new, hitherto unseen facets rolled into view. Spires, arches, buttresses that evoked Gothic buildings appeared and vanished, each in their turn. Curving, swirling lines seemed to fall into existence, then straightened into right angles, contorting immediately afterward into shapes that no mind could fathom but which nevertheless bewitched the eyes.

The feeling of awe that had descended upon him when he’d first viewed a holographic image of the object returned tenfold. In spite of himself, Vaughn had to wonder if he was staring into the business end of another one of the universe’s transcendent, inquiry-resistant mysteries. He recalled the peaceful, floating death-dream he’d experienced after touching a Linellian fluid effigy, a memory that remained green despite being nearly eight decades old. The artifact also brought to mind the life-changing epiphany he’d received from the Orb of Memory, when he had helped recover it from the derelict Cardassian freighter Kamalonly a few months earlier. That encounter had forever altered the trajectory of his life, ultimately leading him to DS9, the Defiant…and finally out here, to confront the ragged edge of the human experience. In the presence of the weird alien construct, he could not help but recall his far more recent sojourn on the world of the Thoughtscape entity, which had forced him to confront the many mistakes he had made as Tenmei’s absentee father. Over his almost eighty years of Starfleet service, he had witnessed enough inexplicable events to credit the notion that some things just might remain forever beyond human ken.

During the Defiant’s approach, the bridge’s population had gradually increased. Vaughn glanced around the room and noted that Shar, Merimark, Gordimer, and science specialists T’rb and Kurt Hunter were all present. Along with Bowers, they stood totally still, staring owlishly at the geometrical contradiction that slowly somersaulted end over end on the screen, a conglomeration of Platonic shapes viewed through a tumbling kaleidoscope.

Vaughn’s feelings of awe were being steadily mellowed by an overtone of caution. He couldn’t help but recall Bowers’ report on Sacagawea’s obviously conflicted feelings toward the ancient edifice that now held the entire bridge so spellbound.

Cathedral. Or anathema.

A hard determination rose within him to get at the truth of it, no matter what it took. Cathedral. Anathema. Either way, the artifact represented the only hope of reversing—or even understanding—whatever changes it had wrought upon his first officer, chief medical officer, and chief engineer.

His friends.

Vaughn saw that Tenmei was already running a series of passive high-resolution scans on the object’s interior.

“Anything, Ensign?” he said.

“Negative, Captain. It’s a blank wall.”

“We’re going to have to work for it, then. Switch to active mode.” He turned to Shar and T’rb, who had already begun busying themselves at a pair of adjacent consoles on the bridge’s upper level. “The moment our sensors turn up the smallest sign of internal activity, I want to know about it.”

“Standard sensors negative,” T’rb said. “It’s like the thing isn’t there.”

Vaughn smiled. T’rb’s off-the-cuff comment was almost literally true, since most of the artifact’s mass lay outside normal space.

“I’m picking up a graviton absorption signature,” Shar said. He sounded almost triumphant, as though he’d just proved a pet theory. “Evidently the object is sweeping up energetic particles and carrying them into its own higher-dimensional spaces.”

“What about positron tomography?” T’rb said to Shar.

“Already engaged.” Shar frowned, his antennae and his gray eyes seeming to work in concert in an effort to bore a hole in his instrument display. “There,” he said at length. “I’m reading a hollow space in the object’s interior.”

T’rb and Tenmei immediately tied their consoles in with Shar’s. They quickly began nodding to each other, confirming Shar’s discovery.

Then T’rb scowled at his readings. “The boundaries of the hollow space seem to be fluid. In motion.”