The Physicist

By gertie_flirty

Fandom: Doctor Who/Big Bang Theory Crossover

Pairing: Slight Sheldon/Penny

Summary: Written for ladyhouston and the Write For Relief meme. Prompt was: "Turns out Sheldon's a Time Lord. He takes Penny along as a companion."

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In Good Time

~x.~x.~x.~x.

"Sheldon, I'm sorry!"

Penny reached out to touch Sheldon's shoulder as he started up the stairs. He paused and turned, glaring at her. He was angrier than she had ever seen him, and she pissed him off quite often.

"'Sorry?' Sorry doesn't un-spill the ice tea you dumped on an extremely rare issue of Action Comics!" He spun around and continued his march up the stairs, with Penny trailing after him.

"Did you ever think you shouldn't bring rare comics to the Cheesecake Factory?"

"So now you're blaming me for your clumsiness."

"No, I was just saying you should've thought it through. I mean, why bring the comic to the restaurant in the first place?"

"I was planning on bringing it to the comic book store to trade to Stuart for a copy of an even rarer issue of Uncanny X-Men."

Penny froze, two steps before they reached the fourth floor. "You mean you weren't even going to keep it?"

He scoffed. "Of course not. It was an investment. Now I have to dig through my collection and find something else to sell instead. It will take hours, thanks to you."

"What do you mean, 'thanks to me?'" she asked indignantly as he opened the door to his apartment.

"Ever since you disorganized them during our prank war, they've never been categorized correctly."

Penny was quiet for a moment. She had really screwed up. "Well, how 'bout I help you sort them out again?"

Sheldon gave her a stern, appraising look. After a long while, he finally relented. "Fine. But wear gloves. And no liquids!"

~x.~x.~x.~x.~x.

And this is how Penny came to be sitting in the middle of Sheldon's bedroom floor (during an absolutely gorgeous Saturday afternoon) surrounded by long cardboard boxes. Sheldon had another set of empty boxes on his side of the room. He refused to let her read any of the comics, even some of them that looked kind of interesting. Penny really wanted to read the Cloak & Dagger ones; they seemed like a cool love story with superheroes.

Sheldon adamantly refused.

She found herself longing to open the flap of those little plastic bags, to slide the books out carefully, wishing she could hear that small swish they made against the board that kept them stiff. To carefully open the cover and smell the newsprint; to look at the vibrant art and read the witty dialogue. To follow the adventures of Spider-man or the Justice League and watch as they defeated evil once and for all.

Dear Lord, she thought. I'm becoming one of them.

"One of what?" Sheldon asked, his head buried in his task by the desk.

She hadn't realized she had spoken out loud. "A nerd."

"Well, you do know a surprising amount of trivia about Star Trek," Sheldon replied, marking down something in a notebook.

Penny stuck out her tongue, but he didn't notice. She sighed and reached into another box and felt something strange. When she pulled it out, she found it was a silver pocket watch. The metal was surprisingly cool to the touch and it had a strange design etched onto the cover.

"Neat watch, Sheldon."

"Watch?" He looked up at her questioningly.

"Yeah, this one." She held it up by its chain so it dangled slightly in the air.

"A fob watch," he said quietly, watching as it moved slowly back and forth. "I've had it . . . since I was a child. But I never noticed . . ."

Penny was a bit nervous. Sheldon's voice sounded far away and dreamy. She wondered if she was hypnotizing him. When he reached out, carefully, his fingers stretched out eagerly, she handed the watch to him readily.

He took the watch in his hand and stared at it intently. A light seemed to come over his eyes, and a breeze swept through the room. Penny began looking around in fright, positive she could hear a voice whispering in the air.

Sheldon ran his thumb over the cover of the watch, feeling the lines grooved into its surface. He raised his finger to the fob at the top and pressed down.

The cover opened and the room filled with a swirling golden light. Penny cried out in surprise and covered her eyes from the intense brightness. She peeked out between her fingers, and the light dissipated quickly.

No.

It was going into Sheldon.

When the light seemed to be completely—absorbed? The thought made Penny's brain hurt. But when the light was gone, Sheldon sat up absolutely straight for a very brief second, then fell over onto the floor.

"Sheldon!" Penny squeaked and did an awkward walk-crawl to his side of the room. Shaking his shoulder, she said, "Sheldon! Sheldon, are you okay?"

He didn't respond and she slowly slid her fingers up to her neck to feel for a pulse. She managed to find it, but the rhythm of it felt weird.

With a loud gasp, he sat up with a jerk, eyes wide. He looked around the room, blinking wildly, until his face seemed to contort into an expression of extreme annoyance.

"Sheldon, what—what was that? What happened?"

He ignored Penny as he lithely jumped to his feet, and began muttering under his breath. "I can't believe it—Earth, of all places, backwards, puny, human-infested, Earth! Now, where is it? It must be around here somewhere . . ."

Sheldon threw himself into his closet, digging frantically through boxes, tossing things off the shelves, throwing his action figures on the ground willy-nilly and stepping all over his comics. Penny hurriedly tried to catch a few of the toys and push the comic books out of the way, pleading with him the whole time.

"Sheldon, what is wrong with you? Did you get a concussion?" These were things he normally didn't allow her to touch, and yet he was treating them as carelessly as wadded-up paper. Something was dreadfully wrong.

"Aha!" He finally cried gleefully. "Here we go."

He gingerly set the object down on the floor. Penny saw that it was a small toy castle. "Your Hogwarts model?"

Sheldon rolled his eyes impatiently. "It's not Hogwarts, it's simply a generic castle of no name."

"Sheldon—"

"'Sheldon?'" His eyebrows arched in surprise, and he scratched his chin in consideration. "It's a good a name as any, I suppose. I never liked the name my people gave me—the Scientist. It didn't even approach the importance of the work I was trying to do—"

"Your people?" A chill ran down Penny's spine.

"The Time Lords," Sheldon replied, bending over to poke at the tiny castle. "If I recall correctly, there should be a button here somewhere . . ."

"What in the heck is a Time Lord?"

"Penny, I don't have time for your ridiculous questions," Sheldon said. "Now, stand back."

In a sort of trance, Penny obediently took three steps backwards. Sheldon pressed down on something on the toy castle then jumped back quickly himself. An electrical hum filled the room, and an intricate webbing of blue sparks surrounded the small model. Thin bolts of violet lightning wove around the castle which seemed to be growing larger by the second. It finally stopped when it was about the size of a child's playhouse.

A bit of dust fell swirled about the room as the crackling fell silent.

"What just happened?" asked Penny.

"I had to reverse the polarity on the Tardis's spatio-reality field. Of course, once I get inside, I can reset the Chameleon Circuit so it assumes a more practical form."

Penny blinked. "I don't know what any of those words mean."

Sheldon sighed in exasperation. He bent over at the waist and opened the small door on the front of the castle and shuffled inside awkwardly, shutting the door behind him.

Penny, her arms still full of toys and graphic novels, looked to her left. Then she looked to her right. She shrugged, shifted the load she was carrying into one arm, bent over and went into the castle.

She was ready to run into Sheldon's bony, awkward knees, or to hit the other side of the castle's wall pretty quickly.

What she didn't expect was what was actually inside.

She was able to stand up straight. The ceiling was nearly twenty feet high, she could have stood up straight at least three times over. And it was huge. At least ten times the size of Sheldon's bedroom, but relatively uncluttered with smooth white walls and a few odd looking portals on the side of the room.

"It's –it's bigger," Penny said breathlessly. She looked towards the center of the large room, where Sheldon was standing in front of a large translucent column. The column had a console sticking out of it, with all sorts of levers, switches, and screens attached to it. "It's bigger on the inside!"

"Of course it is," Sheldon snorted. "It's technically another dimension."

"It's a parallel dimension?"

"No, it's a spaceship."

"A spaceship?"

"And also a time machine, technically."

"A time machine?"

"Yes," Sheldon tapped his foot impatiently. "It's a Tardis."

"Sheldon, that's not a nice thing to call me, I just—"

"No, you idiot, TARDIS is an acronym. It stands for Time And Relative Dimension In Space. Understand?"

"Nope."

Sheldon sighed. "Well, I don't have the patience to explain it to you. I have to get ready to leave."

"Where are you going?" Penny hugged the stack of geek paraphernalia to her chest and moved towards the column.

Sheldon stared straight ahead at a screen in front of him. Unfamiliar symbols and numbers flowed in complicated lines across it, but his gaze remained intense and unfaltering. "To find the man who did this to me."

"Someone did this to you?"

"Yes," Sheldon said, pulling a lever. "The Doctor."