None of his caretakers knew about the gap in the wall; Caz had always been careful to be back in his room by daybreak, and on the rare occasions he’d failed it had been assumed that he was hiding in a nook or cranny in the depths of his pool. He’d been faced with a few pointed comments about how ‘at least the betas didn’t go through a moody-teen phase’, but that was all.
He managed to get his shit together long enough to get out of the water, realign the filter, and tug it away from the concrete until there was enough space to crawl through. From there he could work his way through the warren of maintenance rooms and tunnels that serviced the facility’s multitude of tanks. He gritted his teeth, sent a quick prayer that his trembling legs would hold up, and set off.
Walking helped to ease out the shakes, by the time he had to risk crossing a hallway he was almost moving normally. Almost. He froze at the sound of footsteps, but it was only three betas heading up to bed: Jack, Ace, and Pip paused to give him a trio of curious stares, but when he held a finger to his lips they nodded and carried on their way. His siblings were always more likely to obey him than any human, even Humphries.
The door to the clinic was alarmed, but it wasn’t the only way in. Instead of taking the halls directly towards it, Caz turned left, took a door back into the service tunnels, and scrambled up a pipe into the ceiling where he could walk along the beams. The last time he’d come this way he’d been with Ollie, trying to get a sneak peek at Matteo - long thought dead and only recently found and rescued by the facility - while he was still in quarantine. The long lost parent they’d always day-dreamed about. Until then they’d been told they were clones.
To be fair, Humphries and the other staff-members had thought the same thing. The people responsible had over-promised, and gone to extreme measures to hide their failures. Measures that wouldn’t have even crossed Humphries’ mind.
The metal was cold and rough against Caz’s long, webbed toes, and he hoped that he wouldn’t get caught on a sharp splinter. A bleeding wound would lead to demands for an explanation. Another pang doubled him over; he narrowly avoided landing on the ceiling tiles and crashing through to the floor far below, grabbing the beam he’d been standing on instead. It dug pinpricks into his knees and hands. This wave was different - pleasure tangled up in the frustration, a sharp increase in the ache, but suffused with tormenting glimpses of satisfaction.
And still so much need.
He paused to catch his breath and think. Matteo wasn’t in his usual tank in the main clinic; the storm had trapped him up at the lake, but he’d be brought back as soon as it was over - he didn’t like open water, traumatised by years kept in a glorified fishbowl, but was being gradually introduced to the more sheltered spots as enrichment.
That imminent return meant that logically Ollie would be in a private room, safely tucked away from the only other adult-form nokk. Caz took a right turn and shuffled along the beams until he was over the catwalk that ran above the three smaller clinic rooms, then he pulled aside a ceiling tile and dropped through the hole, landing with a light slap of webbed toes.
Another ripple of hunger almost knocked him into the barrier rail: a repeat of the silky-warm sense of satisfaction, but then a wave of frustration. Whatever his twin was doing wasn’t enough, might even be making things worse in the long run.
Caz listened for any sign that he’d been detected, but all caution fled the moment he spotted Ollie. He slipped under the railing and swung down into the room, then approached the large tank at one end. It was built into the corner, with the back two sides up against the wall, and three glass panels forming a half-hexagon at the front.
Ollie was bound by the wrists: fabric straps attached to a chain, loose enough that he could lie comfortably in the tank, but tight enough to keep his hands firmly above water. A writhing blur of honey-gold, copper, verdigris, and rusty red-black.
Caz paused in front of the glass and swallowed. Once upon a time they’d been identical, members of the first hatched generation of nokker, the new species of human created by an alien device. Even from the start it was obvious that they were different from the others.
Apart from Matteo, the sole survivor of the original changelings, nokker looked mostly human. Normal head, two arms, two legs, all similarly proportioned to their parent species. Typically androgynous, with common patterns among their features from all being descendants of a scant handful of individuals. The most noticeable differences were the venomous spines along their spinal-column and forearms, gill-slits in their rib-cages, and webbing between their fingers and long toes.
Caz and Ollie had almost been able to pass. They’d taken longer to grow than the betas, hitting full size at twelve instead of four, but they were also significantly larger and less gracile, their minds worked more like those of humans, and they could speak out loud. Just add some modified scuba gear and they looked and sounded like two exotic youths. They were designated as ‘alphas’, but they were known simply as ‘The Twins’: Castor and Pollux - though Humphries had nicknamed them Caz and Ollie almost immediately after taking custody.
The smaller, beta nokker were intelligent, but in their own way - one alone was not okay. They functioned best with a hive mind of at least three, and relied on telepathy instead of voice; they learned far quicker than humans, but would rarely figure things out for themselves; and they uniformly hungered for approval. Perfect little worker-bees, ripe for exploitation, which was why Humphries had been so focused on getting them out of reach of profiteers.
Caz and Ollie could at least function independently, and they were far less biddable - downright defiant by beta standards. They were defined as much by their differences to their brethren as their similarities to each other. Two of a kind.
Then Ollie had gotten trapped in a submerged cave, and had changed.
Dr. Humphries had theories, the main one being that the near-constant presence of so many betas, especially unrelated ones, had inhibited the pair of them from moving to the next stage of their life-cycle. As far as adaptations went it would prevent overcrowding and bloodshed. Some truly vicious squabbles had broken out when Matteo had been introduced to a shared tank; a split between betas who considered him family and those who considered him an interloper; between those who thought their role was to protect him, and those who wanted to protect Caz and Ollie, their alphas, from him, whether Caz and Ollie liked it or not. Their obedient natures only went so far.
Humphries thought it pointed to an alpha nokk having to find their own space before taking on their costly adult form, like a male clownfish switching to female only when there was a gap to be filled.
Caz didn’t care about any of the theories. He cared that two out of dozens had turned to one out of dozens. He cared that his identity had been snatched from him by a surprise quirk of biology. He cared about suddenly being one of a kind.
He cared about what he’d have to sacrifice if he wanted to be like his other half again.