“Nice office,” said Donna, looking round the room. “Obviously there's a lot of money in this.”
“Hmm,” said the Doctor, speed-reading a leaflet he'd picked up in the waiting room.
“I suppose people will pay anything when they're desperate,” she went on, assuming that the Doctor was listening to her.
The Doctor pocketed the leaflet and his glasses as the door opened and a middle-aged man stepped into the room.
“Doctor and Mrs Noble?”
“Yes, that's us,” said the Doctor cheerily.
The man shook their hands and then sat down behind an expensive-looking desk. “I'm Mr Franklin. I understand you're here to discuss our services. How can we help you?” He smiled at them in a friendly yet professional way.
“We want a baby,” said Donna.
“Of course.” Mr Franklin looked down at his notes. “Your genomes aren't compatible?”
“Yeah,” said Donna. “I'm human and he's-”
“Martian,” said the Doctor. “Not the Mars near Earth,” he added, “a different Mars that coincidentally has the same name.”
Donna looked at him and then went on. “So we can't have a baby in the usual way.”
“Not that we haven't tried,” said the Doctor.
“Oh, yes,” said Donna. “Morning, noon, and night. I'm surprised he's got any sperm left.”
The Doctor coughed and Donna rubbed his back with wifely concern.
Mr Franklin smiled again. “I understand. Well, I hope we can help you. Do you have any questions about the procedure?”
“How does it work?” asked the Doctor. “Is it just your standard-”
“I'm afraid that's a company secret, Dr Noble. But I can assure you that it's been thoroughly tested and is completely safe. We've got a lot of very happy clients.”
“It won't have three heads or anything?” asked Donna.
“Not unless that's what you're looking for?”
“Just one head will do, thanks. I don't want it getting confused.”
“Do you have any more information on exactly what's involved?” asked the Doctor. “Obviously we've read the brochure but that did leave a few questions.”
“What happens to the genetic material when you're done with it?”
“We can destroy it or keep it in stasis for future reproduction. Don't worry, our security is very tight.”
“He's ever so worried about that,” said Donna. “He doesn't want anyone nicking his DNA. He thinks he's so special.”
“Well, I can assure you that it's certainly never happened before.” Mr Franklin looked at his watch. “Unfortunately, I have a prior engagement. My assistant can discuss sampling, payment schedules, and so on.”
“You've been very helpful,” said the Doctor.
Donna nodded. “I can't wait.”
“Martian?” asked Donna as they walked back to the accommodation block.
“I didn't want to make myself sound too attractive.”
“Right,” said Donna, “cos you really have to worry about that.”
The Doctor shrugged. “People like Time Lords, that's not my fault.”
“How far do we have to go with this?” asked Donna.
“We're not actually going to have a baby, if that's what you're worried about. We just have to get a good look at what's going on here.”
“I still think you're looking for trouble. Like I said, people will pay anything.”
The Doctor shook his head. “There's still too much money going back and forth. And why all the secrecy? Do you have any idea how many documents I had to fake to even get us on the planet?”
“Yeah, but you enjoy that. You like telling lies. It's practically a hobby.”
“That's a bit harsh.”
“I'm just calling it like I see it.” She decided not to push it. “So what now?”
“Now we try to fit in.”
“Does fitting in mean eating? Cos I'm starving.”
“Well, you are eating for two,” said the Doctor, moving out of slapping range before she could react.
Donna had eaten with the Doctor plenty of times, but it had never been a candlelit dinner for two in a posh restaurant. People would talk. Admittedly they'd be saying they were probably a couple, which was their cover story anyway, but the point still stood.
“My first date in ages and it's with you,” she said, gloomily.
“Thanks,” said the Doctor, picking up the menu and putting on his glasses.
“I didn't mean it like that,” she told him. “I meant like... well, this would be really romantic if I was with someone else.”
“I'm not romantic?”
Donna couldn't quite read his expression. “No, you're like my gay best friend. I love you but it's not the sweaty sort of love.”
“Gay best friend,” said the Doctor, trying out the idea. “I don't see what my sexuality has to do with it.”
“I mean, you're not interested and I'm not interested and it never comes between us.”
The Doctor looked at Donna over a glass of water. Finally he swallowed his drink and said “Yeah.”
Donna remembered that they potentially had an audience. “I mean I love you very much, my darling husband, and I look forward to having your baby.”
The Doctor took her hand. “I hope it has your eyes.”
“I hope it has your...” She looked at him appraisingly. “Ears?”
“You don't think I'm handsome?” asked the Doctor, stroking the back of her hand apparently without putting any thought into the matter.
Donna pulled her hand away. “I don't go for aliens.”
“That's what Martha said.”
“I'm not Martha.” Donna shrugged. “If you didn't go for her, I've got no chance.”
The Doctor frowned. “What does that mean?”
“She's gorgeous, in case you haven't noticed. And she's really clever.”
“So are you,” he said.
Donna slapped his hand lightly. “Stop picking on me.”
“I wasn't picking on you!”
Donna looked at him and tried to decide how suicidal he was. Maybe he really hadn't noticed. Maybe all humans looked the same to him. She let him off with a shrug of her shoulders.
The Doctor shrugged off his jacket and threw himself onto the bed. Donna coughed.
“Sharing a bed?”
“Gay best friend,” he pointed out. He propped himself up on his elbows. “Donna, I'm knackered. I couldn't try anything even if I wanted to.”
Donna relented. “I suppose I trust you not to feel me up in the night.”
“Thank you,” said the Doctor settling on his back and kicking off his trainers.
Donna took off her shoes and her jumper and climbed into bed on the other side. She looked over at the Doctor, who was staring up at the ceiling with a sad expression. “Sorry,” she said. “I didn't mean to call you a pervert.”
“It's not that,” he said.
Donna waited for him to elaborate, then realised that he wasn't going to. “Penny for them?”
“All those people, so desperate for children that they'll pay any price and never ask any questions. It's sad. It's tragic.”
“They'll be all right.”
Donna thought for a moment. Then she said, “I used to want children.”
“Not any more?”
She shrugged. “Well, it's not like it's an option if I'm staying on the TARDIS, is it?”
“You might meet someone,” said the Doctor. “Plenty of fish in the universe.”
“And then what? Invite him along?”
“If you want.”
“Nah. Even if I did, you can't raise a kid while living like we do.”
The Doctor turned to face her. “You don't have to stay with me, you know. You can leave any time you want.”
“I don't want to leave. I'm just... I've accepted that I can't have everything. No kids, no proper boyfriends.” She sighed. “I haven't even had a shag since before I met you.”
The Doctor blushed. “Um.”
“The nearest I've got to a bit of fun is when you fell on me last week. And that wasn't exactly satisfying.”
“Should we be having this conversation?” asked the Doctor, slightly desperately.
“Is it making you uncomfortable?”
“Do you want to talk about something else?”
“Can I just sleep?” asked the Doctor, suppressing a yawn.
“Fine, but no copping a feel in the night.” Donna reached over and switched off the light. “Night then.”
Donna woke the next morning to a note on the pillow informing her that she was to meet the Doctor at the clinic. Donna took her time, annoyed at being summoned like that. Then it occurred to her that he might get himself killed, and she hurried along to the rendezvous point just in case.
“I didn't feel you up in the night,” he said when she arrived.
“Good,” said Donna. “So what's the plan for today, then?”
“I want a look at the laboratories.” He led her round a corner and up a fire escape. He patted his pockets until he located the sonic screwdriver, and then unlocked a door marked 'No Entry.' “This might be dangerous,” he warned.
“Well, duh,” said Donna. “Isn't it always dangerous?” She pushed past him and walked through the door into a bland white corridor. “At least it's clean,” she said.
“Better than clean, we're in a sterile environment.” The Doctor opened another door with the sonic and looked in. “Ah! This looks promising.” Donna followed him into a room that looked suspiciously like laboratories always looked in films.
Donna opened a fridge unit and pulled out a jar of something slimy. “What's this?”
The Doctor glanced over. “Seminal fluid.”
“Eww!” She put the jar back on the shelf hastily.
The Doctor shrugged. “It's a fertility centre, what did you expect?”
“I thought they did some sort of posh gene-shuffling thing.”
“They do, but they also do it the old-fashioned way. Not every species is physically compatible with all the others, you know.”
The Doctor gave her a long-suffering look. “Is this really the time?” He put on his glasses and started examining the equipment on the lab benches. Donna decided not to touch anything else, just in case. Finally he looked up. “Why do they need a retro-sequencer?”
“Do you want me to answer that or are you talking to yourself again?”
“Do you know what a retro-sequencer is?” he asked, peering at her over the tops of his glasses.
“It retro-sequences... something.” Donna sniffed. “I can't be expected to understand all your technobabble. For all I know you just make it all up to sound impressive.”
The Doctor stilled. “Did you hear that?”
“I think it's footsteps.” Donna looked quickly round the room. “Cupboard,” she said, grabbing the Doctor by the arm and pulling him towards possible-safety.
It was a small cupboard. It was a small cupboard with mops in. They got into it anyway for lack of anywhere else to hide.
“Are you made of elbows?” Donna complained as she tried to find a position that didn't involve being poked by bits of Time Lord.
“Quiet!” hissed the Doctor, but he shuffled away a bit to give her more room.
They listened as someone moved around the lab, someone who hopefully wasn't a cleaner in need of a mop. Finally they heard the outer door open and shut, and opened the door a fraction to find the lab empty.
“I'm going to need to check the records,” said the Doctor. He found a computer terminal and started tapping away. Donna watched and tried not to touch anything. Sometimes she felt completely useless, and the Doctor was usually too busy to notice. Not that she needed comforting, but it would be nice if he explained what he was doing sometimes. In English. In words of less than seven syllables.
When the door opened she was close enough to duck into the cupboard again, but too far away to get the Doctor out of sight.
Donna didn't like climbing through ventilations systems, but sometimes there wasn't much choice. They always made her feel fat. She tried not to worry about her hips as she navigated towards what she hoped was the room with the Doctor in it. She looked down through a grate to check he was there, and then knocked quietly. The Doctor looked up, saw her, and grinned.
“I've come to rescue you,” she said, looking for a way down. She managed to pull back one of the panels underneath her and then she dropped down, not entirely gracefully, into the room.
“I thought they left a guard at the laboratory?” said the Doctor.
“They did. I used my womanly wiles.”
“You did?” asked the Doctor with obvious surprise.
“I introduced my knee to his bollocks and then whacked him over the head.” She started working on the ropes that held the Doctor to his chair.
“Remind me never to get you angry.”
“These are really good knots,” she said after a while. “It's times like this I wish I hadn't been kicked out the Girl Guides.”
“What did you do?”
“It's a long story and it wasn't my fault.” She stood upright. “I think I'll go and get a knife and then come back.”
She didn't, because that's when the door opened.
They were back in Mr Franklin's office, except people weren't being so polite this time.
“I know what you're doing,” said the Doctor.
“I doubt it,” said Mr Franklin with a rather creepy smile.
“You're not helping people, you're killing them. You're making designer diseases, perfectly tailored to their victims.”
“Oh, that's just for funding. Nothing wrong with catering to the assassination industry.”
“What, you just really like babies?” asked Donna sarcastically.
Mr Franklin ignored her. “Do you really not know, Doctor? The clever Doctor hasn't worked it out?”
“Have we met before?”
“You met my people, not me.”
The Doctor shook his head. “Sorry, not ringing any bells.”
“We had... let me see... wings back then, I think. Very good for aerial attacks.”
“You're a Krillitane?”
Franklin clapped his hands slowly. “I have to say I'm not impressed so far.”
“Aah,” said the Doctor, realisation dawning. “You're harvesting. You don't even need to kill for parts, you can get people to pay you to examine their genetic codes.”
“And is that so bad? Evolution, Doctor. It's not something you can fight.”
“It's also not something you can cheat.”
Franklin smiled. “Which brings us very nicely to your role in all of this. Just think what we can do with Time Lord genes added to ours. Regeneration would make perfect soldiers.”
“You can't do that,” said the Doctor, confidently. “You'd never be able to integrate the parts.”
“Yes, that's why you're going to help us.”
“Regenerating Krillitane. Let me have a think. Um, no. That doesn't seem like a very good idea.”
Mr Franklin sighed. “Fine, I'll just threaten to kill your wife.”
“We're not really married,” said Donna.
“Then I'll kill whatever she is to you, the details aren't important.”
“This is stupid,” said Donna as the Doctor worked on handing over his genome. “I'm less important than all the people they might kill if they can't die.”
“I'm not letting them kill you,” he told her.
“You're impossible sometimes,” she said. “What's happened to your sense of perspective?”
“I need to concentrate,” he said, rather harshly. Donna glared at him and said nothing.
They watched as Franklin injected the new chemicals. “Yes, I can feel the change starting.”
“What did you give him?” asked Donna.
“Everything,” said the Doctor.
“I didn't see any alternative.”
“You... you're thick, do you know that? Thick and stupid and... and thick!”
“We never did pick up sentimentality,” said Franklin conversationally. “We recognised it for the weakness that it is.” He closed his eyes. “I can feel the power of the Time Lords.”
“Yeah,” said the Doctor, “I should probably have mentioned the aggressive nature of Time Lord DNA. Well, I say nature, it's more a design feature. It tends to take over a bit.”
“I'll cope, I'm sure.”
“Except that Krillitanes — the original ones — have a very defensive genome. Anything starts messing with it like that and it tends to... reset.”
Franklin stared at the Doctor. “What have you done?”
“I haven't harmed you,” said the Doctor calmly. “You'll live a good long life as what your people originally were.”
Donna watched in horror as Franklin started to shift and shake. He was almost melting. He wailed and screamed as the change took hold, until all that was left was something like a legless jellyfish.
The Doctor looked at him. “No wonder they're so keen on changing their shape.”
“That was -”
The Doctor grabbed Donna's hand. “Compliments later, now we should run.”
“Aren't we shutting them down?”
“I didn't say we were running away.”
Back in the TARDIS, Donna sat in the crash-seat watching the Doctor fly them to their next destination. “Did you really mean it about bringing someone along if I meet the right bloke?”
The Doctor looked up. “Anything you want, Donna.”
“I'm not leaving, you know. If I don't meet anyone then that's fine.” She shrugged. “Anyway, I've got you to look after. That's enough to be getting on with.”
“And I've got you, my darling wife,” he said with a smile.
“Don't go getting any ideas, Spaceman.”
“None at all,” he said. “None at all.”