"I can't believe you'd kill someone like that, Doctor," Yaz said.
"I had to. When she threatened you and Dan, I snapped. It was bad enough she was preparing to wipe out the entire universe, just to get rid of just one person when she had the resources to be more focused; I actually think along the way, Tecteun had been plotting to destroy the entire universe anyway because she felt her little experiment had failed, so she decided to kill two birds with one stone," the Doctor shook her head. "With that kind of mindset, she was dangerous, Yaz. I've made enough mistakes not doing what's needed in the past, I couldn't let Tecteun continue being a threat."
Admittedly she wasn't best pleased with having to murder Tecteun the way she had, the ancient Gallifreyan scientist who'd once been enthusiastic and curious about the universe Gallifrey lived in only to transform into a cold, soulless woman who stopped caring about the universe and considered it as a giant petri dish which was expendable to the point where she'd have a super weapon she could use at any time…
The fact she even had it was bad enough.
The Doctor sighed, "Tecteun told me she had started the Flux because I knew too much; ever since the Master…captured and put me in the Matrix on Gallifrey to show me the records of the Timeless Child, Tecteun knew I'd look for them. And I did. I scoured the entire universe for signs of Division. I looked for references for any kind of organisation that'd interfered with planets. I looked for agents and I found Karvanistra. He was the only one I could find. And it looks like she might have manipulated Judoon into locking me up in the first place."
"You think that's what happened?" Yaz asked, deciding to ask that the whole mess was to simply kill one person later. It seemed insane, unthinkable, really.
"Yeah. The Judoon got into the TARDIS very quickly. And I wondered over the years I spent in prison how quickly and easily they found me; police box outer shell aside, the TARDIS is not easy to find, to predict where she would land and I'm no exception. Yet the Judoon found me very easily. They also transmatted inside my ship like the defensive mechanism wasn't even there. And they teleported me straight into that prison," the Doctor explained solemnly.
"But," Yaz was quiet as the implications set in, "that means that Division knew the whole time where you were, and when we were."
The Doctor nodded. "The thought occurred to me, too Yaz. The Division was founded originally on Gallifrey, and they have technology seeded from what the Time Lords had. It's not impossible they could track down every single TARDIS that ever existed. With that sort of knowledge, they could have simply sent an assassin and they could have simply killed me in a way that would stop me from regenerating."
Yaz decided to get back to the point where she was amazed Division had done all of this to kill one person. "I still can't believe Division would destroy the entire universe to destroy one person when they could have used another method."
The Doctor nodded although she was startled by how scared she was at the prospect of dying, really dying. "I know," the Doctor whispered. "But it's like I've already said, Yaz, I knew too much and I also think Tecteun wanted to end the universe because her little experiment had gone wrong," she sighed, feeling the weight of years she wasn't even sure about weighing her down, "Tecteun offered to give me my memories back if I rejoined Division and if we abandoned this reality and move to the next, but after everything they'd done, I was sickened she would even make the offer. When I refused she showed she hadn't been sincere in the first place and threatened you, I'd had more than enough of her."
"So you killed her?" Yaz asked bluntly.
The Doctor flinched but she nodded. "Yes," she said breathlessly before she shook her head. "The good news is we reset the universe by shunting the whole Flux event into an alternate timeline, and I've got the device my memories are stored on."
"You have?" Yaz grinned. "That's great!" Suddenly she realised what the Doctor had said. "You….haven't gotten your memories back?"
The Doctor shook her head, looking down.
"But..why?" Yaz whispered, "I thought you wanted them back-?"
"I do, Yaz, but….," suddenly the Doctor sighed, "I'm frightened of knowing what I not only did for Tecteun and Division, but… she hinted I'd lived for thousands of years, millions, and I'd regenerated thousands of times. Until this incarnation, I'd been certain I'd had 13-14 lives, tops. Finding out I've got thousands was a scary revelation for me, and it's even scarier knowing what kind of future I'm destined to have. If I get those memories back, I would likely shrug my shoulders, and accept it. But I can't, not right now! I don't want to be immortal, Yaz. It took me a long time to get used to the concept of regeneration the first time around, and I had lived with the knowledge for years!"
Yaz was silent as she tried to think about how things were from the Doctor's point of view. Not only had her world been shaken up in such a massive way, but she was also being told she had lived longer than she had expected. Was it any wonder she was still reeling? "So…what are you going to do?" She asked hesitantly.
"The device, which looks like a fobwatch, the memories are stored in are safe inside the TARDIS. The old girl was told to keep them safe and sound and will only give them back if I asked. And I trust the TARDIS to keep them safe. She knows how much those memories have affected me. Maybe in another few years, I'll open the device and get those memories, but not just yet," the Doctor said.
Suddenly the Doctor shook her head.
"What?" Yaz wondered what was wrong with her friend now.
The Doctor looked at her hands. "I've lived so many lives, worn so many faces - young and old, middle-aged. But I've always been…comforted that I knew about them; finding out I've lived more lives than the most unconventional Time Lord… it's shocking. One of the reasons I didn't open that watch was because I was terrified."
"What terrified you, specifically?"
The Doctor looked away as she reflected on her thoughts and the feelings she'd had when she discovered she was the Timeless Child. "A long time ago, the Time Lords gave me what I felt was a new regeneration cycle. I was dying of old age, but was the cycle even necessary? Wouldn't I have regenerated at the last minute without Gallifrey helping me? I will never know. But now I know the truth, I don't know how many times I will regenerate now. Will I regenerate forever?"
Yaz….didn't know what to say, because these were questions she had never considered, nor asked herself. Oh, sure, like most humans, Yaz had seen the attractiveness behind immortality, but she was sitting and speaking to an immortal, who had already lived for a helluva long time and wasn't interested in living for even longer, and was confronted with the news she had lived for millions of years and she was confronted with the fact there was still so much she didn't know about herself.
"But that's the worst of it," the Doctor said.
"What do you mean?"
The Doctor's sigh was so world-weary that Yaz felt even more sorry for her. "I came into this universe through a wormhole, Yaz. What if I am thrown into another, and regenerate into a form that helps me adapt to the physical laws of that reality? There's a theory, a very old theory, that a Time Lord's regeneration energy can interact with the energy of a different universe like the one that comes after this one, adapting the Time Lord to the different physical laws. Is that true? Is it possible? I don't know, 'cause no Time Lord has ever been stupid enough to try and travel to the After-Universe to find out. There are so many things that can go wrong. But does my nature mean I will survive there? I don't want to. A long time ago, yeah, I would have been fascinated to explore a different universe, one totally different from this one, and gather new knowledge, but I don't want to now."
A light bulb lit up in Yaz's mind, remembering what her friend had said before. "That's one of the reasons you haven't gotten your memories back. You're worried when you've got your memories back, you will see things differently? That it won't matter?"
The Doctor smiled at her, but while it was a proud one, her eyes were sad. "Yaz, I always knew you had the potential to be a great detective, even with obvious clues. And you're right. That's exactly the problem. Another reason I'm worried about opening that watch is to discover what Tecteun did, and what Division was responsible for. And whatever dirty little secrets are out there. Opening the watch might be a good idea, but I just want my mind to settle down before I do that."
"But you plan on getting your memories back?"
"Yeah, definitely," the Doctor smiled. "If I don't, Division wins by default. They took my memories from me and I vowed to get them back. But," she looked down at her hands, "I'm ambivalent about doing it, especially after what I've discovered, and what I've come to ask myself. How many more times will I regenerate? Do I have an unlimited number of lives, so if I waste half a dozen or fewer of them, it won't matter? If I get my memories back, how much will I change?"
"Doctor," Yaz wasn't sure about what she could say, or if she even should say anything.
The Doctor glanced at her. "In my lifetimes, the ones I remember at any rate," she added with a spiteful twinge in her tone at the reminder of what Tecteun had done, although Yaz said nothing since the Doctor had excellent reason to be bitter, and angry, "I've met dozens of immortals. Jack's one of them, but what is in my future? I know if I open that watch…," she looked down before she looked up into Yaz's face. "You've always wanted to know more about me, haven't you, Yaz?"
"Yeah," Yaz nodded.
When she had first met the whirlwind who was the Doctor, Yaz had been hooked on the mysterious time traveller, and she had tried very hard to learn more about her. Mostly without any luck. The Doctor kept so many secrets from her, and despite her patience, there were times when Yaz wondered why she bothered.
The Doctor sighed and came to a decision. "Face me," she turned her body around.
"What?" Yaz asked in confusion.
"It would take too long for me to say anything, so I'm going to show you telepathically. Face me."
Yaz slowly did as she was told until she was sitting opposite the Doctor. The Doctor took a deep breath as if she were calming herself before she gently pressed her fingers against Yaz's head, with one finger pressed against her temple.
"I'm going to show you my life in your mind, but if you think it's too much then picture a door or a barrier, and I'll stop, but I'll do my best to not overwhelm you, okay?" The Doctor asked in concern.
Yaz nodded. This was her best chance to learn more about the Doctor, and she had no intention of losing it now, but she would do as her friend said.
The Doctor nodded back and closed her eyes. "Contact," she whispered.
Yaz gasped as she felt her mind filled with memories that seemed to stretch forever, and considering how long the Doctor had lived, that was not a surprise. The Doctor hadn't been exaggerating, it was overwhelming. In a flash, she saw her friend as a child, a little boy, looking into the Untempered Schism after living with his family for several years. She saw the Doctor going through the Academy, and hated every minute of it. She saw her friendships with young children with one of them being the Master. She saw her mistake with Rallon and Millennia, and how she had eventually escaped once she got the willpower back after thinking it was lost.
Yaz had never felt so much pain and loss and yet profound wonder speeding through her mind as she saw everything the Doctor and Susan (his/her granddaughter!) saw in the TARDIS, the exile on Earth in the 1970s, her mistake with the Daleks, and all the way through with the Time Wars - the first with Faction Paradox, the Council of Eight, and the Daleks. All the way through to the current moment in her life. And all the time, Yaz felt that the Doctor was trying to keep her safe from being overwhelmed, and for that she was grateful.
The Doctor pulled away at last and held her face in her hands. "I have 2-3,000 years worth in my mind, Yaz, I don't think I can fit in anymore."
Yaz didn't say anything, she just wrapped her arms around her friend.