Last thing we saw was a pin-striped arm, yanking Tom Milligan into the TARDIS, rescuing him from the wiles of the ever-creepy Sylvie. What now?

TEN

"Jesus, mate," Tom breathed as the Doctor yanked him through the door, and locked it against the angry, piercing railing of Sylvie on the other side. "I wasn't sure how long you were going to make me go. Another minute and I'd have…"

"I know that you'd have, but you didn't," the Doctor said. "That's kind of the point. Now, don't move. I know it sounds daft, but just stay in that frame of mind."

"What frame of mind?"

"The… you know… aroused frame," the Doctor said, eyes wide with discomfort, and a degree of alarm. "Just brace yourself, let it take you."

"You want me to…"

"To?"

"You know!"

"Oh," the Doctor said, surprised. "You mean, finish what she started?"

"Yes!"

The Doctor thought about this. "Actually, it's not the worst idea," he said, moving round the console now. "You can pretend I'm not here."

"No I can't!"

"Fine, just close your eyes, and think of Sylvie. Just a minute ago, what she was going to do…"

"Okay, but… why?" Tom whined.

"Because, it's the easiest way to get your energy signature," the Doctor said. "There's a reason why Sylvie's kind's M.O. is the mind-bending shag. It gets your temperature up, your adrenaline is high, you're on the verge of bursting, of course they can absorb your energy easily. And so can my sonic screwdriver."

"Ugh. Fine," Tom sighed. Reluctantly, he turned away from the Doctor, and did as asked, and after a few moments, the Doctor aimed the sonic at him.

"Oh, she's good," the Doctor said, listening to the high-pitched buzzing of the device. "She's got you glowing like Alpha Centauri."

"Yeah, that's her spécialité," Tom muttered. "Been on-edge all night."

While Martha had been talking with Sylvie outside, buying time, the Doctor had studied the nest, using nothing more than the TARDIS' camera system. He'd seen the electrical equipment all around the room, that probably ran the lights and unmanned kiosks for the carpark adjacent. In that mess, he'd spied a panel on the wall that definitely did not belong on this planet. He'd expected to find a dome-shaped, bulbous, perhaps pulsating, red power centre. But it was, in fact, disguised, compressed, and camouflaged in the electrical-works, so that the average human happening through the room would not notice it.

He also saw that there were two wand-like apparatuses that were connected to the power centre. He knew what they were being used for, but he tried not to think about it... for now. He'd get to them in time.

And just before pulling Tom through the door, he had instructed the TARDIS to dial into that power centre, interface its energy, and stand by.

The Doctor had left her and Alain to the electrical devices of the Cervovores. Chaos was ensuing all around her – she and Alain had each received another shock, and another one was coming in a few seconds.

For a minute or two, Sylvie had been lurking about the blue box, trying to figure it out, kicking and punching at the door, and/or trying to find another way in. Suddenly, though, she began scream once more and bang her fists against the wood.

And when the next shock came, a split second beforehand, Martha saw the TARDIS begin to glow. Her body then experienced the expected sharp pain and spasm, but then, after a second, miraculously, the pain abated and was replaced by warmth, and calm. It was a familiar sensation… the TARDIS' energy (and something else) was interfering with the electrical shock.

And then the whole sensation retreated, and she could hear Alain nearby, panting, and asking "What the hell…?"

The TARDIS was still aglow, as were the shock-wands that Jean-Marc and François were using, and the wires connecting them to a panel on the wall. Not surprisingly, the panel was glowing, too.

Sylvie turned and looked all of the glowing, then began to scream, "Noooooo!"

Her male counterparts reacted in very much the same way.

Martha noticed absently that François was now a six-foot-tall, beautifully-sculpted, naked man, no longer the creature they had met upon arrival. He had now shocked her two-and-a-half times…shocking her must have been enough to give him at least a temporary humanoid form. And of course, this form had to be attractive enough to gather energy signatures from some unsuspecting, long-term object of his relentless lust…

Sylvie's panic reached a fever pitch as she, herself began to glow, and when this happened, she went to her knees again, groaning in pain and protest. Something like lightning seemed to shoot through her, and suddenly, it all stopped. When the glow retreated, she looked exactly like François had looked a few minutes ago: short, globular, frog-like, enormous-mouthed, head like a fish.

This was what the Doctor had needed Tom for! He had duplicated Tom's energy signature while he was aroused, so he could us it to leech Tom's particular energy out of the Cervovores' power centre! Sylvie's humanoid form was being held steady with Tom's energy – without this, she was powerless, and had to revert to square-one.

When Sylvie stood up and realised the state of affairs, she screamed even louder, and threw herself against the TARDIS door, threatening both the Doctor and Tom, swearing to have both of their heads. Martha noticed as Sylvie slammed her body into the wood that the Cervovore's skin was practically liquid. She was a bit surprised that François had initially had the corporeal integrity to even hold electrical wand steady enough to…

And then another shock came. She screamed in pain and surprise, and could hear Alain beside her, doing the same thing. The next shock came in quick succession…

Jean-Marc and François were seeing what had happened to Sylvie, and were panicking.

Another shock. Then another!

"Careful!" the Sylvie-thing shouted at them. "Humans are frail! If you do that too much, you'll kill them before you're ready to harvest!"

And thus, the shocks stopped for a few moments, and Martha and Alain had time to catch their breaths. Martha reached out for him, and he took her hand. When he looked at her, she could see his nose bleeding. She now realised hers was as well.

"You okay?" she mouthed.

"I think so," he whispered.

The Doctor and Tom stumbled out of the TARDIS then.

Jean-Marc and François charged them both, and what ensued was something that Martha had never seen the Doctor nor Tom engage in before: a full-on, knock-down, drag-out, punch-up. She could see well enough that the "good" guys were trying to get to her and Alain, but the "bad" guys were not about to let them.

Martha took the opportunity to try and move. She crawled over to Alain.

"Alain, pinch up here," she said to him, pinching her own bleeding nose, as a demonstration. He got up on his knees, and obeyed. Then she asked him, "Have you got any numbness anywhere?"

"No," he said, turning his head awkwardly to see her.

"Tingling?"

"No," he answered, after seemingly assessing how he felt.

"Can you see all right? Any spotty vision?"

"My vision is fine."

"And you can hear me all right?"

"Yeah, if you don't count the…"

With that, Jean-Marc's body came crashing into him, knocking him sideways onto the floor again. Tom had managed to get the advantage, having wound up, and given the humanoid a swift, hard kick to the midsection, toppling him. Tom should have used this moment to grab Alain by the arm, get him to his feet, and away from the fray. Instead, he looked back and forth between Alain and Martha, for a crucial two seconds of indecisive delay.

In the end, Tom went for Alain, but he was a second too late, and was struck down. Jean-Marc grabbed his ankle as he dived forward, and his head hit the concrete floor with a thud.

"Ow! Shit!" he cried out.

The sickening sound the impact had made was a trigger for Martha. "Tom! Oh my God!"

"What?" the Doctor cried out, picking himself up off the floor after being elbowed in the chest, hard, by François. "What's happened? Is he all right?"

François took a swing at him, but the Doctor ducked.

Martha scrambled to get to Tom, but he turned and got up on his own.

"Don't move! You might be…" she began.

"I'm fine," he said to her absently, now also ducking a blow from Jean-Marc. He stumbled backwards toward François, who saw an opportunity to charge him.

The Doctor now had one of the electrical prods in his hands. François took a running start at Tom, but the Doctor moved quickly and touched him in the shoulder with enough volts to make him scream for five seconds, and drop to the floor in pain.

As Jean-Marc wound up to deliver another blow to Tom, to everyone's shock, Alain took up the other electrical prod, and stabbed Jean-Marc in the back with it. Twin screams now filled the air, and both male Cervovores were temporarily writhing in the floor.

"TARDIS! Now!" the Doctor screamed.

Alain was mesmerized and horrified watching the two men (now starting to recover) in pain. He dropped the electrical wand, and stared at them with wide, disbelieving eyes.

The Doctor and Tom were already at the TARDIS, ready to enter, when a piercing, daemonic cry came from nowhere, and Sylvie, in all of her frog-fish-like glory came from behind the vessel, and attacked Tom. Her entire bubble-like body was now wrapped around Tom's left shoulder and head, and he yelled, trying to peel her off.

François and Jean-Marc were getting to their feet now.

Before they could quite gather their faculties, Martha took up the electrical wand, and shoved it into Sylvie's side, shocking both her and Tom. Their unison screams filled the space, like a pair of sirens. After three seconds, she pulled it away, and Sylvie was still twitching, and making trembling, growling noises in her throat. She had no choice but to let go of Tom, and fall to the floor, in a liquid-like mass of grey, almost non-corporeal flesh.

Tom was, literally, in shock, and stumbled backwards. The Doctor caught him under the arm, and threw open the TARDIS door with one foot. For the second time that night, he physically hauled Tom Milligan through a doorway, away from angry Cervovores. Martha grabbed Alain's hand just in time, and they all stumbled into the console room, cutting it fine, and locking the door behind them.

"Oh, my God… wha…" Alain began to ask, as he looked around the interior of the vessel.

"Not now," Martha snapped at him. To the Doctor she said, "Okay, now what?"

"Now, we try to reduce Jean-Marc to the same jelly-monster that Sylvie has become," he replied, amidst the sound of two aliens-cum-Frenchmen outside, throwing themselves against the TARDIS, and cursing at them.

"How do we do that?"

"Extract Alain's energy from their power centre, just like we extracted Tom's" the Doctor said. "Except… it might not work because the majority of his humanoid energy came from Gregoire."

"Who's Gregoire?" asked Tom.

"My boyfriend," Alain told him. "He died tonight."

Tom frowned, even as the screams and thuds outside became nearly deafening. "Killed by Jean-Marc? Oh, I'm so sorry."

"Yes, it seems Gregoire and Jean-Marc had a destructive, co-dependent, semi-violent, but mind-blowingly satisfying relationship for years before this nice man came into the picture," the Doctor said to Tom, putting an arm around Alain's shoulders in a gesture of camaraderie. "Jean-Marc followed him all over the world."

"Oh!" Tom said, his eyebrows high with alarm. "Whoa, now I see!"

"Yeah, so, shouldn't we try to get Gregoire's energy signature, if the majority of the time, he is who Jean-Marc has been targeting?" Martha asked the Doctor.

"We can't," he replied, moving toward the console. "His energy signature was extinguished when his heart stopped pumping and his brain stopped working. Alain is all we've got now."

"What chance have we got of reverting Jean-Marc to alien form using Alain?" she asked, her voice high and desperate. Even she could see that it wouldn't work as well as using Tom to cut Sylvie down to size. It couldn't work as well.

"None," said the Doctor, pulling some sort of device out from the compartment underneath the controls. "But we've got a shot at keeping Alain from being his next prey. Jean-Marc already has to start over with a new victim, with Gregoire gone. He'll begin working on someone else fairly soon… if we don't extract Alain's energy…"

"He'll start working on Alain," said Martha.

Alain looked at all of them as though he were waking from a dream. "Oh. Well, I won't let him. I know what he is now."

The Doctor looked at Alain squarely, and shook his head. "He's already got his hooks into you. You've been with him sexually, yeah? And he got another healthy dollop by shocking you."

"How's that?"

"The Cervovores' consciousnesses are connected to the power centre, and the power centre is what gave you the shock," the Doctor told the man quickly. "And, bad news, the energy transfer works a little bit both ways – it's why Gregoire was never able to resist him. It's why Tom, you were never able to resist Sylvie. They are magnetic. They don't play fair. And their sexual prowess is tailor-made to keep you lot in line. It's almost like… software."

"So I won't be able to escape him? He'll just pursue me like the Terminator and keep getting me to shag him, then eventually eat my head?" Alain asked, panicking.

"If we don't stop him, there's a good chance, yeah," the Doctor said. "Which is why I'm hoping this will work."

Screams and shouts continued outside the TARDIS, though it now sounded like they were getting tired.

The Doctor showed Alain the thing he'd pulled from the console's hidden cabinet. It was a blue, light-metal bar in the shape of an isosceles triangle, except one of the sides of the triangle was split. The Doctor pulled the split open and approached Alain with it, clearly hoping to place it on his head.

"What's that?" Alain asked, staying still, though he was nervous.

"It's an energy amplifier of sorts," the Doctor said. "And it's going to be tight."

The two sides of the bar now rested on Alain's temples, and he winced, but did not complain. The Doctor plugged it into the console.

"What does it do?" Alain wanted to know.

"Well, the best way to get an energy signature from someone is to get them excited… you know, the way Jean-Marc and Sylvie operate. Fever-pitch excited, preferably. But I don't see that happening with you, Alain, so I'm hoping that fear might give us the same result, with a little help from the amplifier here."

"Oh. Will that work?" the worried man asked.

"Only one way to find out," the Doctor said.

But Martha could tell from the look on his face that the Doctor didn't like his odds.

Well, I hope the pseudoscience bits are clear - the mechanics of energy-transfers, and how they got Sylvie to revert to her original form, and whatnot.

In any case, leave me a review... but especially if there are parts you don't get! Thank you for reading!