four

Martha, Nina, and the Doctor walked secretly to the lab, where they were testing Larazus's DNA on the computer. As soon as the results appeared on the screen, Nina and the Doctor gasped, mesmerized at the sight before their eyes.

"That's..." the Doctor trailed off.

"Amazing," Nina finished for him, getting slightly closer to the screen just to be sure of what she was seeing.

"What?" Martha asked, confused. She hadn't yet seen what the Doctor and Nina were seeing.

"Lazarus's DNA," the Doctor said.

"I can't see anything different," she frowned. Nina pointed at one strand of her DNA, making her fix her eyes on it.

"Look at it," the Nina told her. Then, right before their eyes, the piece of gene mutated. It changed.

"Oh, my God," Martha exclaimed, taking a step back. "Did that just change?" Nina and the Doctor nodded at her. "But it can't have," she frowned.

"But it did," the Doctor confirmed.

"It's impossible," she denied.

"And that's two impossible things we've seen so far tonight," the Doctor said, a goofy grin on his face. Nina could only smile at him. "Don't you love it when that happens?"

"That means Lazarus has changed his own molecular patterns," Martha guessed. Nina froze, raising her eyebrows in surprise at Martha.

"She's good, I like her," Nina smirked at the Doctor. "Hypersonic sound waves to destabilize the cell structure, then a metagenic programme to manipulate the coding in the protein strands. Basically, he hacked into his own genes and instructed them to rejuvenate." Martha raised her eyebrows too.

"You're good too," Martha said. The Doctor was just standing in the background, admiring the conversation between the two girls, who apparently didn't need him to find out what was going on. "But wait, they're still mutating now," she pointed out.

"Because he missed something," the Doctor finally spoke. "Something in his DNA has been activated and won't let him stabilize. Something that's trying to change him."

"Change him into what?" Martha asked, looking at the two in confusion. The Doctor and Nina shared a look, both looking for an answer, and then their faces fell when they realized the other one also had no idea.

"I don't know, but I think we need to find out," the Doctor said.

"That woman said they were going upstairs," Martha remembered.

"Let's go."

The three of them entered the elevator, and Martha hit the button to the top floor, where Nina was mostly sure the professor would be. Rich guys who owned buildings often loved the top floor more than the others, she knew that from experience. She was pretty sure the top floor would be his office.

As soon as the elevator dinged, they walked outside.

"This is his office, alright," Martha said, noticing the desk and the miniature palace standing in the middle of the room on a table. The Doctor turned on the lights.

"Told you," Nina told the Doctor, who hadn't had the tiniest bit of faith on her hunch. He squinted his eyes at her when he saw the smug smile on her face.

"So where is he?" The Doctor asked.

"Dunno," Martha said, looking around. "Let's try back at the... reception." When she paused, the two TimeLords perceived she had seen something. They looked at where her eyes were fixed upon and realized there was a body behind the professor's desk.

As they got closer, Nina noticed that the body's liquids had been sucked out, it had been mummified. Still, by the clothes, hair and face format, they could yet recognize the dead woman on the ground.

"Is that Lady Thaw?" Martha asked as they walked to her. The Doctor crouched on the ground next to her head, and it was only then Nina realized he was wearing converses. He was wearing a black, formal suit, and a pair of black converses. I mean, she knew TimeLords had a dreadful fashion sense, but that was just a tiny bit too far. Next thing she knew he could be wearing food as an accessory.

"Used to be," the Doctor confirmed. Martha scoffed in horror.

"Now it's just a shell," Nina said, crouching down next to the Doctor. He looked at her for a second, wondering how she could be crouching down only on her feet without losing balance, and only then realized she was wearing black heels. He kind of stared at her for a second before snapping out if it when she continued to speak, realizing he had been staring and she had probably noticed it. "Had all the life-energy drained out of her."

"Like squeezing the juice out of an orange," he panicked. Nina frowned. The Doctor mentally slapped himself.

"Not the comparison I would have gone with, but yeah," she said. They locked eyes for a second before Martha spoke.

"Lazarus," she whispered.

"Could be," the Doctor said, feeling himself go back to his normal self. Not that there was anything normal about him.

"So he's changed already," Martha tried to guess. Nina thought back on the DNA sample they witnessed change back at the lab.

"Not necessarily," she told her, shaking her head. The Doctor stared into Nina's eyes, realizing what she was thinking.

"I know, the DNA was fluctuating," he continued. Nina nodded.

"The mutation process must demand energy," she guessed. "This might not be enough." And only then she grasped what she had said. And so did Martha.

"So he might do this again?" Martha exclaimed, panicking. The Doctor shrugged, not bowing exactly how to answer.

The trio immediately stood up and ran to the elevator.

They got out of the elevator into the reception, walking through a couple of violinists. They walked around the room, looking for Lazarus, or as Nina so affectionately called him in her head, Mr. Old Man.

"I can't see him," Martha told the two. Nina found herself being the sarcastic little shit she once was, using jokes and humor to go through stress and feelings.

"Of course not, you're five feet shorter than everyone else in this room," she said.

"You're literally shorter than me," she shot back.

"Can we not argue about this now?" The Doctor asked them.

"You have no day in this, you're two heads taller than everyone in this room," Martha said. Nina found herself loving Martha more and more everytime she spoke.

"Just keep looking," he mumbled.

Suddenly, Nina felt an enormous wave of pain go through her head and her knees went weak. She fell into the arms of a tall man, her hands her temples.

"Miss, are you alright?" A voice asked. It said something else, but it was muffled like it was very far away. Nina recognized the voice as Leo's, Martha's brother.

"Nina?" There was another voice, a woman's voice. Nina still had her eyes closed. She was afraid the light from her surroundings would worsen the dreadful pain in her head. "Doctor, something' wrong."

Nina saw the Doctor, his eyes burning, shining with a white light, as he screamed in pain. Nina could almost feel the pain he was in, only by the expression on his face. He was wearing an orange astronaut suit, but not the helmet. Nina watched as his expression suddenly fell, and he looked at her directly in the eyes. She listened, unable to do anything, as a voice that wasn't the Doctor's spoke to her through his mouth.

"Burn with me."

"Nina, I've got you," a voice brought her out of her thoughts. She felt her headache suddenly lessen as she grabbed onto the hands that held her face. "Open your eyes, let me see you," he asked her.

Nina slowly opened her eyed, finding the Doctor's brown eyes staring at her worryingly. She frowned when she realized what had happened. He had used his regeneration energy on her. It was absolutely stupid to use it on her, he might need it soon, he couldn't possibly know.

"Did you just-"

"Just stay here," he cut her off, not wanting to be yelled at at the moment. "I'll be back." And with that, he ran off to the elevator, Martha following him close behind. Nina wanted to go after them, but she knew very well her legs wouldn't be able to keep up, not at the state she was now. Nina felt a warmth wash over her when she realized that she had a tuxedo thrown over her shoulders; it was the Doctor's.

Nina looked around, finding out that the Doctor had left her on Mother duty. Martha's mother was standing next to her, and so was Leo, her brother. He was looking at her worryingly, his hands ready to catch her if she were to fall.

"Are you alright?" Leo asked her. Nina sighed internally as she got the picture that she would have to babysit while the Doctor and Martha went in an adventure. She liked going on adventures.

"I'm fine, thank you, Leo," she said, a kind smile on her face. "I've got this killer fever today, though. Definitely should have stayed home." Nina looked over at Martha's mother, who seemed only slightly worried about Nina, and mostly not believing a word of what she said. She obviously didn't like Nina and the Doctor very much, she didn't trust them.

"Why did you come, then, miss-"

"Jones, believe it or not," Nina said, a small chuckle leaving her mouth. "I couldn't possibly miss Mr. Lazarus' experiment, could I? Also, I was promised free drinks."

"By the Doctor?" She asked. Nina got a feeling that she was under interrogation, but decided to go with it, not appear too suspicious, because it wouldn't be good for her nor for the Doctor.

"Oh, yes. Old friend if mine," she said, a smile on her face. "We come from the same town," she improvised. "Met him when I was a child."

"Oh really?" Martha's mother asked. Nina could see that she was starting to believe what she was saying. Try spending 50 years of being a slave for Hydra, you end up learning how to lie properly. "Where are you two from?"

"Ipswich," she said from the top of her head. Nina had absolutely no idea where Ipswich was, didn't even know if it was a real place. Nina suddenly grunted and squinted her eyes as another - less intense wave of pain went through her.

"You came in with a medical student and a man who calls himself the Doctor," Mrs. Jones said. "And as you almost fall to the ground in pain, the two of them ran away, leaving you behind," she reasoned. Damn. Nina had to admit she had a point. Nina didn't really know how to respond to that, and just shrugged as she wished the Doctor was rushing back to save her from mother duty.