A/N: Barely made it on Tuesday. Totally on schedule.

Last bit of exposition before we get more...action? Drama? Something.

Chapter 6: Wibbly Wobbly, Timey Wimey

After overcoming his reservations, Rintaro did his best to recount everything. He began with his discovery of D-Mails, and discovering Kurisu's dead body. The Doctor said something strange about that — "Ah yes. Introducing someone by killing them off. Must be a time travel thing." Rintaro didn't know what he meant by that, and frankly he didn't want to, so he kept going. He covered how he found Kurisu again, the formation of the Future Gadget Lab, working on the D-Mails and the Time-Leap Machine, and recruiting Suzuha and Moeka. With great difficulty he pushed through the part where SERN broke in and killed Mayuri. He covered going back in time and trying to save Mayuri before undoing all the D-Mails. Mayuri gripped his elbow as he tried to still the quaver in his voice; the Doctor set his beaker tea down and leaned forward as he told this part. Skipping a few…extraneous details, Rintaro finally got to the part where he reached what he called the "Stein's Gate" ending, saving both Mayuri and Kurisu from certain death. Kurisu, noticing his haggard expression, took over from there, explaining how she and Rintaro reunited and how she returned to working for the lab.

"We're based in Akihabara, but we're in Mitakihara right now for a physics convention. I thought —" she quickly glanced at Rintaro, "— I thought we could use a change of pace."

The Doctor got up and began pacing. Nardole chuckled.

"You're doing the thing," he pointed out with a grin.

"Shut up," the Doctor retorted without looking at him as he continued pacing.

"What thing?" Mayuri inquired.

"The thing he does when he's impressed, and is considering the most non-committal way he can express it," Nardole replied. "I think in Japan you'd call it…tsundere?"

"That sounds right," Itaru affirmed. "Right, Kurisu-chan?"

"H-how should I know?!"

The Doctor whirled around. "Nardole," he hissed, "if you tell them that I'm impressed, it defeats the whole purpose of me trying to hide that I'm impressed."

"That is my purpose, sir," said Nardole, his eyes twinkling.

The Doctor passed a hand over his face. "So you exist solely to frustrate me," he sighed. "I've always known."

"Only in some things," Nardole corrected. "And anyway, who reassembled me, again?"

"Don't remind me," said the Doctor, a hand still over his eyes, "I'm having regrets."

"Second thoughts, sir?" Nardole placed his hands over his chest in mock astonishment. "I'm offended."

"Oh, we're way past second."

"Sorry, what?" Kurisu cut in. "'Reassembled?'"

"Oh yeah," said Nardole, "I'm a cyborg."

Kurisu threw up her hands. "Of course you are," she said, collapsing back into the armchair. "And he's an alien. Of course."

"They even account for fixed points…" the Doctor muttered. He shook his head before finally resuming his place in the chair he'd borrowed. "Okay, I am impressed," he admitted without sounding too happy about it. "You got some stuff wrong about how time works, but you got a lot more right than most people. Passing grade."

"What did I get wrong?" Rintaro asked.

"What you call 'attractor fields,'" said the Doctor. "Well, it doesn't sound wrong, per se. The terminology is a little off, but it's a decent understanding. It's just incomplete."

"What's missing?"

"Me," said the Doctor. "Oh, and I guess Nardole too."

"Thanks," Nardole grumbled.

"According to your research," the Doctor explained, "what people call 'parallel' or 'alternate universes' are divergences from a central timeline. Starting from the same path, what you call 'divergence points' create branches, and some of those branches get grouped together into 'attractor fields' – timelines that share a singular event in common. A 'fixed point,' if you will."

"That's…right," Rintaro confirmed.

"But I can see them all," the Doctor continued. "All those branching timelines, those 'attractor fields.' And they don't add up."

"Hang on. What do you mean you can see them?" asked Kurisu. "You can't 'see' timelines."

"Maybe you can," the Doctor replied, "but I can. I'm a Time Lord. It's in my blood."

"He's rusty, though," Nardole amended. "He needs a computer to check his work. And I check the computer, so technically I check his…" Nardole fell silent as the Doctor shot him a pointed look.

"Anyway," the Doctor continued, "short version: if attractor fields are like the branches of a tree, and timelines are like the twigs on the branches…then there are currently three trees superimposed onto each other."

"Three trees?" Rintaro repeated. "Like, three different timelines?"

"If we want to be more accurate, I'd call them universes," the Doctor corrected. "Timelines and attractor fields are essentially variations of the same universe. But your universe has no variations that make it look like mine. And vice versa, my universe will never vary in such a way that it looks like yours.

"Let me show you what I mean." He pulled his sunglasses out of his jacket pocket and held them out toward Rintaro. "Put these on." Rintaro was puzzled, but at this point there was no good reason to refuse; he took the glasses and put them over his face. He immediately gasped. What he saw was not a tinted view of the apartment common area, as he had expected, but was instead a glowing array of swirling, connected golden lines, pulsing at irregular intervals. They all seemed to branch off of one larger, central line like twisted ribs coming off of the spine.

"What is this?" Rintaro asked.

"A psy-quantum time-map," the Doctor answered. "Downloaded it from the TARDIS before I came here."

"That's just a bunch of gibberish," Kurisu protested.

"I'm pretty sure that last name is offensive," Itaru tried pointing out.

"Mayushi wants to see!" Mayuri exclaimed.

"Would you all just shut up for a second?" the Doctor snapped. "I'm trying to have a decent chat about the multiverse."

"You'll get a chance later," Nardole whispered in Kurisu's direction. "You'll love it. Or hate it, maybe."

"Nardole," said the Doctor, "don't make decisions, it doesn't suit you. Now, Mad Scientist –"

"Hououin."

"What?"

"My name is Kyouma Hououin," Rintaro declared in a suddenly grandiose voice, leaping to his feat, "and on this day I hereby dub you an honorary member of the Future Gadget –"

Kurisu got up as well, and slapped the back of his head.

"Sorry," he said, sitting back down, "got carried away there. But you should see this, Christina. This is amazing. It's lightyears ahead of the Groogle Glass."

"It's not Christina," Kurisu reminded him as she sat back down. "And you look stupid."

"Don't diss the specs. Specs are cool." As soon as he'd said this, the Doctor slapped his forehead. "Ugh. I thought I'd moved past that. Anyway, that there is a map of your universe and its various timelines. Take a look at it and try to find an event that you know took place in the timeline you're currently in."

"Find…?"

"Just think of it."

"Oh." Immediately a node lit up on one of the branches, and it zoomed in to show a scene from Rintaro's memory: that of meeting Kurisu on the bridge, with her starting to recover her memories. It was from a third-person perspective, though, which was just a bit disturbing.

"Now try to find an event that you know happened in another timeline," said the Doctor. "Preferably in another attractor field."

Rintaro tried not to think about it, but there was really only one event that would come to mind first. When another node lit up on another branch, he tried not to wince at the sight of Mayuri's lifeless body lying in a pool of blood, a bullet shell lying nearby.

"You will even be able to see events that you've only heard about, but did not encounter directly," the Doctor added. "Past or future. No matter which attractor field."

Rintaro looked for World War II, and sure enough, he found it – in startling and disturbing high definition color, as opposed to the black-and-white by which it was normally portrayed. Then, after some thought, he remembered what a certain part-time warrior told him about World War III. Sure enough, that came up as well.

"Now," said the Doctor, "try looking up the Time War."

Rintaro concentrated, but no node lit up. Instead, a message appeared on the lenses in front of him: Event not found. Search other universes?

"Anything about UNIT?" the Doctor inquired. "The Racnoss Formation of Earth?"

"What the heck are those?" Kurisu asked.

Event not found, the message repeated. Search other universes?

Yes, he thought. The branching golden lines disappeared, and a new, similar structure appeared, but blue instead of gold. Several nodes lit up at once, and Rintaro saw scenes that he neither recognized nor understood: weird round metal robot-things pouring out of a flying saucer; a swirling galaxy growing rapidly larger and brighter; an entire planet vanishing in the middle of space. More and more images appeared of a foreign man with a cap and mustache holding up a pistol, and a strange, crystal-like spaceship surrounded by spinning rocks.

"None of those events happen in any of the attractor fields of your universe," said the Doctor. "But they're all essential events that happened in my history. That's how you can tell that there are different continuities – different universes – at play here."

Rintaro took off the glasses. "Here," he handed them to Kurisu, whose face was twisted with consternation and a thousand questions, "before you blow a gasket." Kurisu glared at him, snatched the glasses away, and put them on. Immediately her face went slack-jawed. "Whaa…?"

"Suddenly so eloquent," the Doctor remarked. "There's not only two, but three such universes overlapping each other right now. Supposedly separate, but now occupying the same time-space. That's not supposed to happen."

"Is that bad?" said Mayuri.

"Bad? Oh, not at all," the Doctor replied. "Unless you think the end of all time, space, life, and existence might be a minor inconvenience."

"Oh…" Mayuri looked like she still didn't get it.

"Parallel universes in contact are volatile," the Doctor continued. "I'm sure you know what the consequences of uncontrolled interference in history might be? That's why I've got to find a way to extricate those universes as fast as possible, before they ruin each other."

"But how would we even do that?" Rintaro pointed out. "Actually, how would you even combine parallel universes anyway?"

The Doctor snapped his fingers and pointed at him. "Now somebody's asking good questions," he said. "Which is frustrating, because I don't have good answers. I've ruled out the only people I know who could. Meaning whoever it is, is…new."

"That's why he went looking for you," Nardole finished, nodding at Rintaro. "When he found out you were a time traveler, he thought you might be involved in whatever was going on."

"How did you know that, anyway?" Rintaro asked.

"All time travelers carry some residue of vortex energy," the Doctor explained. "You're covered in it. Saw it with the specs."

"Vortex energy?" Mayuri repeated.

"It's like dust," Nardole offered. "Like, erm…magic…dust."

"Fairy dust," Mayuri breathed.

"That's not what I said," Nardole protested.

The Doctor scoffed. "Grow up, Nardole. Fairy dust looks completely different."

"I've undone all the alterations I made to the past," Rintaro said slowly, "and I haven't time-traveled for months. Well…not of my own doing." He looked toward the Doctor. "You said you saw the storm, too. Was that time travel? What caused it?"

"Technically," the old man answered, "your Time Leap, and whatever caused that little jump earlier, are less time 'travel' and more like a time 'reset'. Instead of one person moving with respect to time, time moves with respect to the people – us. As for who caused it…I was hoping you would be able to answer. You're my only lead, you see."

"Was," said Nardole.

"What?" The Doctor turned to him with furrowed, striking eyebrows.

"'Was' your only lead," Nardole clarified. "Don't we have someone else to look into now?"

"What did I say about correcting –" Suddenly, the bushy grey eyebrows shot upward, and the eyes below them widened. "Oh. Ohh! A miracle! Nardole, with a good idea!"

"Hey!"

"By the way, it's 'were,' not 'was.' Ha!" The Doctor shot off the armchair and snatched the sunglasses off of Kurisu's face ("Hey, wait!" she protested). "I'm not done with you yet!" he declared, pointing behind him toward Rintaro as he strode toward the door.

"Where are you going now?" Rintaro asked, also standing up.

"Middle school," the Doctor replied. "Yuck."

Rintaro frowned. "But it's Sunday!"

The Doctor looked back at him and grinned. "Time Lord, remember?" Then he was gone, and with a wave and a smile, so was Nardole.

Rintaro looked at Kurisu, who was still blinking her eyes, bewildered at the sudden removal of those impossible glasses. He looked at Itaru, and then lastly, he looked at Mayuri, who gave him a questioning look.

In his head, a voice in his conscience whispered, Time travel started this whole mess.

Another voice responded, But now it's dragging us back into another mess. The only way out is through.

And then a third voice, louder and clearer than the first two, finished with, I have to know. I have to see a real time machine.

"Everyone," he said as he approached the door, "don't wait up for me."

"Where are you going?" Itaru asked.

Rintaro stopped and turned with a dramatic flourish of the long white lab coat he was wearing. "Tomorrow," he declared, before opening the door and exiting the apartment.

Immediately, Kurisu was on her feet. "Both of you, stay here," she commanded. Then, she too stepped outside.

"Is Kurisu-chan gonna stop Okarin?" Mayuri asked Itaru. "Or is she gonna join him?"

They sat in a couple moments of silence pondering the question. Then, in wordless agreement, they stood up and made for the door.