As she dropped slowly into the increasingly claustrophobic passage, she recalled the Dax symbiont’s experience inside the mysterious “cathedral artifact” the Defiant’s crew had discovered in the Gamma Quadrant. Ezri and Dax had been separated for a short time, and the unjoined Dax symbiont experienced a horrific, solitary vision that Ezri Dax now recognized as a premonition of the recent parasite attack on Trill. This unsettling encounter had brought the symbiont face-to-face with all of its previous hosts, each of whom had carried dire, oracular warnings—and had accused Dax of negligence in preparing for what was to come. Dax had surmised that the mystical, almost nightmarish experience had been precipitated as much by symbiotic interruption as by Audrid’s painful memories of the alien thing that taken the life of poor Jayvin.

Dax’s boots settled at last to almost level ground, and she saw that the passage had narrowed to the point that her suit lights had no trouble illuminating the walls in any direction; every crack and crevice stood out in sharp relief. As she moved forward, half walking and half swimming, the passage wound and twisted and narrowed until she thought the wide upper portion of her environmental suit might get her stuck.

Any symbiont that manages to make it this far down has got to be hunchbacked,she thought with no small amount of gallows humor. Even if she were able to raise Cyl or the runabout’s computer, she knew that an emergency beam-out to the Rio Grandewould have a very low probability of success. The very geological features that protected the symbionts in the caverns from long-distance transporter kidnappings would kill her if she were to become trapped down here.

Dax continued following the tunnel’s gentle downward slope for perhaps another twenty minutes, her suit’s metal-ribbed shoulders scraping disconcertingly from time to time against the sides of what had become a nearly horizontal tube of fluid-filled rock. For several minutes, she was literally crawling on her belly through yet another ancient lava tube. On top of this difficulty, the steadily increasing water pressure was pushing relentlessly against her suit, making its joints stiff and unyielding. Her thighs and arms ached with exertion, and exhaustion was threatening to overwhelm her. Still, her suit sensors indicated that something—something alive and symbiont-like—lay an indeterminate distance ahead.

Fortunately, one of her helmet lights revealed what appeared to be a ledge only a few meters ahead. Beyond that ledge lay what looked like another one of Mak’ala’s large, open pools. A gentle current seemed to be pulling her in that direction. She heaved a sigh of relief at the prospect of getting out of the narrow passage soon.

Wrunch.

Once again, both of her shoulders had come into sharp contact with the alarmingly tight rock walls that bracketed her. Fortunately, the suit wasn’t pouring oxygen bubbles into the water, so its seals hadn’t been compromised. Then she noticed the true gravity of her predicament.

Stuck. Damn!

Fear kicked her hard in the belly; she knew that the intense pressures at this depth made it extremely doubtful that a symbiont would notice her plight and carry word of it back to the Guardians. And even if the Guardians somehow did become aware of her problem, they wouldn’t be in a position to do anything about it.

Forcing down an impulse to make matters worse by hyper-ventilating, Dax simultaneously called upon the expertise of two previous hosts: Emony, among whose skills were agility and deep-breathing exercises; and Curzon, who’d been nonpareilin the fine art of complex extemporaneous cursing.

Neither was of much help. She was jammed in tight. And her injured hand felt like it had caught on fire.

After perhaps a minute of fruitless pushing and disciplined breathing, she recalled the time Torias had performed an EVA to repair some meteor damage to a shuttle he’d been piloting in low Trill orbit. Matters had gotten very complicated and interesting when his environmental suit malfunctioned, causing portions of it to expand like a balloon. In pretty short order, his suit had become larger than the shuttle’s hatchway, trapping him in the airless void outside. Ezri realized she had no choice now other than to employ the very same risky-but-elegant solution Torias had improvised that day.

She felt around on her chest-mounted keypad until her gloved fingers came into contact with her suit’s manual valve control. A few seconds later, a spray of bubbles flooded the narrow stone tube. She heard another sharp wrunchas her suit contracted slightly and her shoulders came loose. Moving her feet in tandem in a flukelike motion, she quickly developed enough forward momentum to traverse the two meters or so that separated her from the end of the passage. Then she tumbled languidly into the vast pool that lay beyond it.

As she scrambled to close the valve before too much of her air supply bled away, she was relieved to find herself descending into a much larger chamber, though her lights told her little else about her new environment. Her weighted belt drew her steadily downward, and she noticed a conspicuous lack of both symbionts and their conversational energy discharges. It was as though she were floating in the same featureless white void Benjamin Sisko had described to her when he had recounted his “visions” of the wormhole aliens.

Then her boots once again made contact with a hard, irregular surface. Because her lights were revealing little of value about her surroundings, she turned them off, just as Taran’atar had done back in the frigid cavern on Minos Korva. Whiteness instantly gave way to blackness; Mak’ala’s weak but persistent currents and the stone beneath her feet were the only proof that anything in the universe existed other than herself.

Eventually her dark-adapting eyes picked up the slender flicker of blue-white energy in the distance. It looked distinctly like the communications impulses that the symbionts passed between one another. But these exchanges lasted significantly longer, almost like lightning magically trapped in amber. The colors of these energy spikes were subtler than the discharges of the symbionts, layered in countless variegated hues.

Unsure how far away they might be, she moved toward them, trying not to dwell on the ever-burgeoning pressure at these depths; the fluid that surrounded her seemed increasingly intent on crushing her environmental suit flat.

After an interval that might have lasted ten minutes or an hour, she felt she had come nearly close enough to grab the slow, stately energy discharges in her gloved hands. The rocky surface upon which her boots had settled took on a smooth, almost paved feel, ending at a gracefully curving section of rough stone wall that rose several meters over her head and curved away into the darkness. The stone wall had an almost scaly texture, and exhibited an eerie greenish glow that brought to mind recollections of Minos Korva, as well as memories of the ice comet that had brought Audrid such pain and horror.

Spying a sudden, furtive movement on the periphery of her vision, Dax turned toward it. Her jaw dropped in incredulity as she realized she was standing perhaps a meter away from the largest symbiont she had ever seen. Though the creature had the same overall vermiform shape of the symbiont that dwelled within her, it was nearly two meters in length. Lit by Dax’s wrist lamps, the giant symbiont’s bulk reminded Dax of a Tenaran seal, or a manatee that Emony had seen during a visit to one of Florida’s Gulf Coast estuaries on Earth. Somehow, Dax maintained the presence of mind to run a quick scan of its RDNAL profile, which revealed it to be a good thousand years older than any other known living symbiont.

Dax was startled further when a flash of blue light lanced from one end of the creature and into her abdomen. Simultaneously, a voice, filled with equal parts indulgent humor and idle curiosity, sounded inside her head and seemed to reverberate all the way down through her midsection.