A/N: This story features the REG!Nine Doctor from the BBCi story, The Scream of the Shalka.

Infections

"You're drunk." The Master, sitting comfortably in one of the armchairs by the fireplace, didn't even bother to look up from his book.

"Nonsense!" protested the Doctor, stumbling towards the console. "I've merely been sampling the local produce." Alison followed him into the TARDIS, a few steps behind, her arms weighed down with parcels.

"Might I ask why you allowed him to get into this state, Miss Cheney?"

"He's not my responsibility," she snapped, putting the packages down. "He said he didn't want to 'play tourist' -"

"And promptly found the closest public house whilst you..." he raised an eyebrow as he looked at the number of parcels, "...went shopping. How nice. He must have ingested a great deal of alcohol for it to have had this sort of effect on him."

"What are we going to do with him?" asked Alison, looking at the Doctor, now slumped in a chair. His eyes closed.

The Master shrugged. "Do what you like, Miss Cheney. I'm going to my room, as he will undoubtedly start snoring and it's not a pleasant sound, I can assure you. Good night." With that, he placed a marker in his book and put it down on the table beside him, before standing up.

"Good night," she said quietly, as he left the console room, closing the inner door behind him. She stared at it for a few moments, once again puzzled at the Master's behaviour.

Glancing at the Doctor, she could see that he was breathing, always a good sign, and apparently asleep. Probably the best thing to do would be to let him sleep it off, and make sure he drank plenty of coffee in the morning.

She grinned to herself. Notwithstanding this little incident, it had been a good day. After all, she had gone shopping on an alien world. It wasn't quite the universe saving adventure she had been expecting, but it was a start.

And with that thought keeping her company, she picked up her packages and made her way to her own room on the Doctor's ship.

"Did you sleep well, Miss Cheney?"

"Fine thanks. You?"

The Master raised an eyebrow. "You might recall that I am an android."

"Oh. Right. Sorry." The Master inclined his head slightly and returned to reading his book. Another book. Always books. With a cup of tea and two slices of toast.

Alison was tempted to ask how he could eat if he was an android, but she doubted he'd give her a straight answer anyway. Instead, she made her own breakfast, and noticed the lack of unwashed dishes in the little room that they used for meals. So, the Doctor wasn't awake yet. Or he hadn't had anything to eat, which wasn't exactly unusual.

She had just finished making coffee, when the door burst open and the Doctor strode in. Scowling.

"What happened yesterday?" he demanded, looking at the Master.

"You don't remember?" asked Alison.

"Of course I remember," he replied. "I was drugged!"

"You were drunk," said the Master mildly.

"Rubbish, and you know it. I'm never drunk. What did you do?"

"Don't be ridiculous. And, besides, I remember you being drunk on several occasions. Especially memorable was the time you decide that a good – "

"All right, all right!" snapped the Doctor. "But I don't get drunk I now ." He paused, glancing at the freshly brewed coffee "Hurry up and eat, Alison, we're going back to investigate why I was drugged."

"This is entirely you're fault."

"I never touched the controls!"

"You I always touch the controls. And fiddle. And adjust. And reorganise ."

"I improve."

"It's worked perfectly well for over one thousand years. It doesn't need to change now."

"Of course not. Let's see how far we get on positive thinking, shall we?"

They glared at each other across the console. Alison stood to one side, her eyes flicking from one face to the other. She began idly betting against herself as to who was going to look away first.

Finally, she sighed. "Can't you just put in the co-ordinates of the planet we were on?"

The Doctor looked uncomfortable. "I would. But I can't quite remember where we were."

"Because you were drunk!" The Doctor shot the other Time Lord a glare.

"Doesn't the TARDIS keep a record of where you've been?" asked Alison, trying to find a sensible solution.

"Yes, normally. But he's wiped it."

"I was tidying up the system!"

"Well, don't you remember where we were?" she asked the Master.

"My dear, I haven't the time or inclination to keep track of the Doctor's wanderings across the universe."

"You've time to mess about with my TARDIS though!"

Alison sighed, her patience at an end. "I hope you two sort it out. I'm going to feed my Truzzkai."

There was a moment of silence, and she could feel their eyes turning towards her.

"Your what? "

---

"Isn't he adorable?" Alison had brought the small creature through to the console room. She sat the cage down on the table by the armchairs and peered through. The little ball of fluff within was sitting quietly, apparently quite content.

The Doctor stared at it. "What did you say it was called?"

"They guy who sold it to me called it a Truzzkai. Said they made good pets. Well-behaved, quiet, easy to take care off." She glanced down it again. "And very cute."

She heard the Master groan.

"It looks harmless enough," said the Doctor. He poked a finger into the cage, but the creature didn't react.

"Of course it is. Why would the shopkeeper lie to me?"

"You mean apart from the fact that he recognised you as a naive, somewhat overwhelmed tourist without a great deal of experience on alien worlds?" asked the Master.

Alison rolled her eyes. "Come on, it's just a pet."

"It's very suspicious," muttered the Doctor. "I was drugged, and you were sold an animal that doesn't exist."

"Are you always this paranoid?" asked Alison, folding her arms as she stepped between the creature and the Doctor.

"My dear Miss Cheney, he's quite correct. There is no such thing as a 'Truzzkai'."

"Look, I know you two are Time Lords, but that doesn't mean you know everything."

The Master let out a sigh. "Truzzkai is the first person present tense of the verb truzzkan. Meaning, to fool. At least it is in the Akosba language used in nine of the twelve planets in the Rintaron Alliance. Someone has been playing with words. Foolish and arrogant"

"And you'd know all about that," said the Doctor.

Alison ignored his comment and said, "Oh right, because with the infinite possibilities in the universe, there's no chance that anyone is going to use the same word twice to mean two completely different things."

"Valid point, Alison. But there's also the fact I've seen these creatures before on Rintaron Prime. They weren't called Truzzkai. In fact they didn't have a name. The government was using them as a form of communication."

"How?"

"Not entirely sure. Was a bit busy bringing down an upstart tyrant at the time." He reached over to the cage, but Alison stopped him before he could touch it.

"What are you going to do?"

"Don't worry, I just want to take a closer look," he said. When she didn't move, he added, "I promise I won't hurt it."

"Doctor, are you sure this is a good idea? Your curiosity- "

"Is one facet of my fascinating personality. Yes, I know that. Now let me see..." He reached over to the latch on the cage and flicked it open, then rolled up one sleeve and reached inside. The creature made a noise of protest as he clasped it in his fist and took it out.

"Now what?" asked Alison.

"A little examination, I think," said the Doctor, but before he could take it anywhere, it began to squirm furiously. A moment later, and it had slipped from the Doctor's grasp. "Alison! Stop it!" he shouted as it pelted across the floor at a phenomenal rate, chased by the Doctor and Alison.

The Master followed them at a much more relaxed speed, " I did tell you," he murmured, but not loud enough for either of his companions to hear.

"It's heading for the console!" exclaimed the Doctor, sprinting across the room, his long strides quickly overtaking Alison.

"But why?" she asked between breaths. "What's it want?"

"Don't particularly want to find out."

"I thought curiosity was one of your best features," she said. He didn't reply, but instead, in a last desperate attempt to catch the creature, launched himself across the floor in a mighty jump, hands outstretched, fingers reaching forward.

He missed, and hit the console with a crash, before falling to the ground.

"Are you alright?" asked Alison as he reached him and offered a hand to help him up.

"Fine," he replied shortly. "Where did that thing go?"

"I think I saw it go inside the central column."

The Doctor turned to the console and began to operate the controls, a frown on his face.

"If you want to be useful!" he called to the Master. "Come and help!"

"And what, exactly, would you like me to do?" asked the Master smoothly as he joined the other Time Lord at the console.

"Check the systems for any anomalies."

"If you insist."

A moment later the TARDIS lurched to one side. The Master and the Doctor instinctively held on to the console, but Alison found herself thrown across the room.

"Ow," she complained, rubbing her arm as she got to her feet.

"Try to find something to hold on to," the Doctor told her. "That may very well happen again."

"Now this is interesting," murmured the Master.

"You mean the way it's interfacing with the TARDIS programs. The word I'd use is destructive."

"But it's adapting at an incredible rate, replicating itself, feeding of your systems. Almost like a-"

"Virus!" exclaimed the Doctor. "That's what that thing was! An actual physical computer virus."

As Alison made it back to the console and wrapped her fingers around the rail that was attached to it, the ship shook again. Less violently this time, but that didn't seem to reassure the Doctor.

"I've isolated the unaffected systems," said the Master.

"What about navigation?" demanded the Doctor, not looking up from the console.

The Master shook his head. "Intact. But not under my control. We appear to be rematerialising in real space/time."

"What!? Let me see!" The Master stepped aside, allowing the Doctor to see that status of the TARDIS's systems. "Out destination is being altered...and what is that?" He pointed one thin finger at a panel that was glowing softly, a stream of numbers running across it.

"We're emitting a signal," said the Master. "I was trying to shut it down."

"What sort of signal?" asked Alison.

"A homing beacon," muttered the Doctor, rubbing his temple. "It looks like your charming pet was designed to physically connect with a spacecraft and take it to a specific point in space, while emitting a signal to alert someone to its progress."

"What for?"

"Piracy, most likely. Unfortunately the TARDIS isn't a normal ship. And this virus is harming the intelligence that is already there," the Doctor told her.

"You mean this thing's sentient?"

"Not..." he broke off, and closed his eyes. "I can feel it," he murmured.

"Doctor?" He didn't respond. "Doctor!" She glanced at the Master, who was still busy at the controls, and then slapped the Doctor across the face. Hard.

His eyes snapped open, and he was glaring down at her. "What was that for?"

"You were out of it," she told him. "You need to get that thing out of the TARDIS."

He was silent for a moment, glancing around the console room. "It's getting darker in here," he said. She looked around. It was always pretty gloomy in this part of the TARDIS. Just enough light to see what you were doing. Mostly she found it rather depressing, though she could appreciate how the Doctor might find it restful. He was right though, at the moment she couldn't see the bookshelves, and it was difficult to make out the details of the fireplace. She shivered, and tried to tell herself that it wasn't getting colder.

"Just your imagination," she said, trying to sound hopeful.

"I'm afraid not, Miss Cheney," the Master said. "The architectural configuration is being manipulated by the virus."

"We can fight it, but it's moving too fast. The manual interface is too slow." He glanced at the Master.

"I don't like what you're suggesting, Doctor."

"I'd do it myself, but last time I check, I was organic. And you are just as dead as us, when that thing starts warping the part of the TARDIS we're standing in."

The Master threw a look over his shoulder. Alison could see the darkness closing in around them; it was an almost physical presence. If she looked hard enough, she was sure she could see it moving, and twisting, like it was alive. She was tempted to step away from the console, to reach out and touch it.

"Unless you have another suggestion?" snapped the Doctor.

"Very well," the Master agreed.

Alison watched in an almost morbid fascination as the two Time Lords began to connect the Master to the TARDIS. The Doctor had retrieved a toolbox from under the console, and was currently connecting some sort of instrument to the circuitry inside an open panel, whilst the Master had peeled back the skin from his left forearm, and was quickly connecting wiring to his own circuitry. She found herself staring at his exposed arm. Most of the time, she forgot that he was a machine; he seemed so human. And yet that too was a lie, and he'd probably be insulted by the suggestion.

The Doctor finished his work at the open panel and glanced at the Master.

"Ready?" he asked.

"Not quite."

"Well, get a move on!"

"You try attaching this primitive circuitry to yourself!"

Alison found the bickering almost comforting, though now it carried an undertone of worry. From both of them. The pale light from the console lit up the Doctor's face, too many shadows played around his features, and Alison noticed that the warm light that the roundels normally emitted was gone. And so were the roundels.

She knelt, trying to see how the darkness merged with the floor. It was moving, edging closer.

"Alison, keep back," the Doctor told her.

She stood and took a step back. "Is it...real?" she asked, not entirely sure what she meant.

"It's as real as any other variation of the console room," replied the Doctor. "Unfortunately I doubt very much that it has the atmosphere to support life."

"So if I stepped out there...?"

"I'm not sure," he said. "You wouldn't last long."

He turned away and looked at the Master. The other Time Lord nodded.

The Doctor turned a dial on the console, and Alison could hear a high-pitched hum of power. The Master's eyes closed and she saw his left hand clench and unclench. He frowned, though she didn't know if it was from concentration or pain.

"Could it infect him too?" asked Alison.

The Doctor glanced at her, looking uneasy for a moment. "It's possible." His eyes returned to the console.

"Doctor!"

His head jerked up, and he saw Alison pointing at the Master. His eyes were still closed, but the darkness surrounding the console had reached him, and it was spreading along his right arm, winding around it like a snake.

The Doctor's hands moved furiously across the console. His eyes narrowed and flicked towards the Master every few seconds.

"Alison, come to this side of the console," ordered the Doctor. "And be careful, don't let it touch you."

Alison nodded and holding onto the rail that ran round the console, she edged towards the Doctor. As she reached him, he flicked a switch, and the shadow around the Master's arm faded, as a tendril of darkness appeared opposite Alison.

"I'm afraid I can't get rid of it. But I do still have a very limited control left over the internal architecture," he said with a grim smile.

"Right," she said. "But is it working?"

"He needs time to understand the mathematics of the infection," said the Doctor. "Time to form an attack."

"We don't seem to have much time," muttered Alison, her back pressed against the console.

"Nor can we afford to make a mistake," said the Doctor quietly.

She could feel it now, just in front of her face. Cold and dark and suffocating. Too close. Too close.

She closed her eyes.

Ice rushed over her limbs, so cold it was burning her skin. She tried to breath but her muscles wouldn't work. She couldn't open her mouth, couldn't move her ribcage. Couldn't scream. She needed to move, to panic. But she couldn't see.

Couldn't feel. No sensations, but the vague awareness that nothing was there. Floating. Falling.

Sound rushed through her ears. Like she was standing under a waterfall. Still, nothing touched her skin.

Nothing except a hand.

A warm hand touching hers.

"Alison?"

She opened her eyes and found herself looking at the Doctor.

He was smiling.

She was sitting up in one of the armchairs by the fireplace, propped up by cushions, the Doctor kneeling by the chair, his eyes full of concern. A fire was blazing in the grate, and she was grateful for the warmth. For a few seconds, she let herself be distracted by the dance of the cheery orange flames.

"What happened?" she asked, her throat sore, her voice croaking painfully.

"It past through you. Just for an instant. I'm so sorry." He paused. "But you're going to be fine. The Master managed to eliminate the virus."

"Is he...?"

"I'm perfectly well, Miss Cheney. Thank you for your concern," said his smooth voice.

She tried to move, but the Doctor stopped her. "You're still weak. You're systems had quite a shock. You should rest." Alison nodded, and the Doctor passed her a cup of hot tea.

"Here," he said. "Will cure practically anything."

"It was my fault, anyway," she murmured taking a sip.

She saw him glance at the Master, and a moment later, the android Time Lord sat in the armchair opposite her.

"I don't think so, my dear," he said. "As I discovered while attacking it, the virus was designed with a very specific purpose in mind: to eliminate TARDISes."

"But why? Who would do that?" asked Alison sitting up. "And how would they know that you were on that planet anyway?"

The Doctor sighed and with a scowl aimed at the heavens, said, "We may not have arrived on the world that I intended. It is entirely possible that they redirected us to a destination where they believed that a threat was being developed against them. I suppose you were spotted as being the easiest way to get it aboard the TARDIS to test. And I was drugged to make sure I didn't notice the danger."

"Are you sure?" she asked doubtfully. "It all sounds a bit...unlikely."

"Indeed, but at least this way the Doctor has an excuse for his lack of restraint in that bar," said the Master.

The Doctor ignored him, and said, "I think we've earned a break at any rate. You certainly aren't going to be in a fit state for saving the universe for the next few days."

"Do they always watch you?" she asked, sipping at the tea. "Always send you into danger like that?"

"No. Not always," he said. "You should try to sleep." And with that, he stood, leaving the room alone.

Alison glanced up at the Master, still sitting opposite her. His eyes were closed, and he seemed...peaceful. It occurred to her that the look didn't entirely suit him. She coughed, gently, and his eyes opened, fixing on her.

"Thank you," she said.

The Master shrugged. "A matter of survival, Miss Cheney. I was in as much danger as you and the Doctor."

"But you're an android," she said. "Surely you don't need as sophisticated an environment to survive."

She caught the hint of a smile on his face, before he leaned forward and lifted the teapot from the little table by the fire.

"More tea, Miss Cheney? I see that your cup's empty."