The specimen looked like granite; milky and crystalline with an odd, greasy sheen to it, shot with cracked veins of white and purple. Quartz or possibly nephaline… it was difficult to tell.

Nyssa wasn't going to move closer to find out.

She held the scanner gingerly before her, squinting to read the mercurial display, trying to decipher the alien symbols shifting upon its surface. The unit was squashed and wrinkled, like a metal plant root. Occasionally a tendril leapt out to snipe at her fingers and she'd let out a yelp. Everything around her was strange. Nothing here was safe.

Nyssa shook her head and moved to the next specimen, shuddering as the rock behind her rumbled deeply at her departure. It wanted her. She knew that. It made her grateful for the Cyber-technology that maintained the force fields. Which was a peculiar feeling indeed.

The next specimen was smaller, although it still towered over her, with a large crystalline head and an angular, sweeping body. Its weapons and limbs had been wrenched off, leaving awkward stumps, scarred with savage cracks that ran deep into its body. Cyber-tentacles were bolted onto the surface of the specimen; others twisted and burrowed in through holes drilled into it by force-cutters. The force fields that restrained it did nothing to dampen the creature's howls of anguish and misery.

Nyssa stared at the scanner again, but couldn't focus her attention on it. At least they'd left her alone in here. There were no guards, no hideous, mutant Cyberman... no mutated Adric. She was... alone... Alone. Her whole body trembled again, quaking. Initially, when she'd first been brought here, the sheer scope, the sheer audacity of the research smothered any emotion other than fascination. Allowed her to forget… to forget…

She desperately wanted to forget.

But she didn't know how…

And now she was torturing innocent creatures… creatures that she couldn't even name…

"It's a Kroton."

The scanner flew across the room, clattering into the darkened recesses of the vast chamber as Nyssa jumped with surprise. "Doctor!"

The Doctor was bent over the side of the chamber, half-hidden in the shadows, examining controls that squirmed and melted beneath his fingers. "Only a SDS-level scout unit though… Hmmmm….I wonder… Don't worry, they can't detect me… but could you turn that off? It's giving me a headache."

"What? Oh." Nyssa reached deep into the pocket of her khaki overalls and flicked off the distress signal. It was one of the few items she'd managed to grab from her desk before… "I was afraid to use it; I was afraid it might be a trap..."

"Well, it would be, I suppose, if they hadn't already killed me." T he Doctor looked up at her with a quick glance. "They haven't tried to convert you."

Nyssa wasn't sure if it was a question or a statement. "No. At first I thought it was to lure you into a trap, or perhaps…" Perhaps Adric was still in there somewhere, trying to protect her. But she didn't say it. She knew it wasn't true, couldn't be true. "But they haven't converted anyone from the station who had been infected by the Lazar's disease."

"No… they wouldn't… alters the configuration of the neurons… not very compatible… Damaged goods, in most cases I'd imagine." The Doctor kept mumbling as he moved to the next specimen. " Goodness me! An Ogri."

"Doctor…" Nyssa paused, not sure how to say it, but knew that she had no choice. "Doctor, it's Adric. He's alive, but... They've converted him."

The Doctor turned from the Ogri to stare, his full attention focused on her.

"Or, at least I think, after conversion, he converted them." She hated to speak it but could think of no other possibility. Adric's knowledge of mathematics, coupled with what he'd learnt of the TARDIS and block-transfer computations, in the hands of the Cyber-host... she shivered. "They're time-active now, Doctor," she saw the creatures again in her mind, the silver twisting slugs that writhed and hissed. She'd seen them dive in and out of time and space on their scanners, wriggling through the vortex, infesting people and planets up and down along the length of their timeline. "They don't need bodies or ships any more; they can absorb any metal or organic matter, any creature…"

The Doctor nodded curtly, as if somehow, he had other matters on his mind. "I did notice some irregularities on my scans… among some other things I've seen recently. It would explain their temporal abilities. They never possessed the elitist attitude the Daleks maintained towards other species... a distinct, if horrific, advantage…" He returned his attention to the creatures. "And now, it would appear, they need your assistance with tribiophysics in converting- or rather, harvesting," he corrected, "silicon-based life-forms… fascinating. Have you made any progress?"

Nyssa glanced around the floor, searching for the discarded scanner. "Little… It's only a matter of time though, with or without me… When they brought me in, I saw thousands more laboratories like this one, all working on similar specimens…" Her voice drifted off… something else was bothering her, but she had refrained from asking. There could be a hundred different reasons why she wasn't here: she could have finally gone home, moved on or be safe inside the TARDIS. But Nyssa doubted it.

"Doctor, please, let's get out of here." She hated how her voice sounded in that moment, so pleading, so young, but she couldn't take much more. She felt old, weak. Worn.

"Yes, of course. Well, sort of. You see, I have a plan." He gave her a wink then and, for a moment, Nyssa felt her heart glow, as it used to, once so long ago now.

It gave her the courage to ask. "Doctor, where's Tegan?"

"She's dead." He said it so quickly, so sharply before diving back down to the alien panels again that Nyssa hoped she'd misheard him.

But, deep down, she knew it was true.

"I never said it was my plan… Nyssa, I'm afraid I'm going to have to ask you to do something that you won't like…"