(I don't own Jimmy Neutron or Doctor Who, but I do know Keith Alcorn!)

Jimmy's brain was his blessing, but also his curse. It seemed he was always thinking. Thinking all day, and even at night, plagued by insomnia as he lay awake in thought. Sleep always took him in the end, but even then, he kept on thinking. Thinking, and thinking. Thinking in his dreams. And more often than not his dreams became nightmares.

Always thinking, thinking. Thinking every morning, after a long night of troubled sleep and ceaseless thought. The first thing Jimmy did every morning was think. His brain was like a supercomputer, but with no off switch.

Jimmy's brain was his blessing, but also his curse. It seemed he was always thinking.

His eyes shot open, now. He stared up at a strange, asymmetric ceiling. Had he seen this ceiling before? What room was this? He didn't know.

He didn't know. Jimmy's brain seemed to have halted. He perceived in his own mind, for the first time — as far as he knew — a stillness. This, itself, was not a thought, for his thoughts had been put on pause. But rather, a passive observation. His mind was totally at peace, and this filled him with unbearable dread.

Jimmy sat bolt upright, desperately trying to kickstart his brain. He inhaled sharply, tried to exhale but failed, and inhaled again. His lungs strained against his ribcage, refusing to inflate further. Jimmy felt on the verge of panic. He let out the breath and, just as quickly, took another. Finally, Jimmy's brain offered up a feeble thought, the first since he'd become conscious in this strange place.

I might hyperventilate.

Recognizing how close he'd come to a panic attack, and thankful for the return of his ability to think, Jimmy began to calm down. He closed his eyes, tried to granulate his panic into manageable chunks.

Where am I? Jimmy thought.

He looked around and beheld a room which looked utterly foreign to him. It certainly wasn't his bedroom. For one thing, he wasn't in his bed. He was on the floor, lying on a cold metal grating. Swiveling his head side-to-side, his eye was drawn to what he imagined was this center of the room. He saw there a floor-to-ceiling column, surrounded by what appeared to be multiple control panels. A haphazard collection of knobs, buttons, and switches, the function of which he couldn't even begin to guess.

Panic seized him again. Jimmy's thoughts — his memories — flooded back to him. Not all at once, but enough, and with sufficient force to jar him back to lucidity. He sat up straighter, bracing himself for what he had to do next. Summoning all his strength and all his willpower, Jimmy pushed himself off the floor of this bizarre room. He stood up, took another look around him, and a single word crept into his mind.

TARDIS.

A nonsense word, Jimmy thought, and yet… And yet Jimmy was somehow certain he did know the word. He knew its great and terrible meaning.

"Why can't I remember?" Jimmy said out loud. The question confused him. He didn't think he had amnesia. Yet he couldn't shake the feeling that a chunk of his memory was missing.

"Ok…" he said, preparing to conduct a kind of self-diagnostic. "My name is Jimmy. Jimmy Neutron. James Isaac Neutron, actually. I live in Retroville. I'm 11 years old. My best friends are Carl and Sheen. My worst enemy is Cindy. And I'm a—"

Jimmy choked on his last word. He was about to say "genius", yet this self-descriptor felt him with a dread he could not explain. He took a step toward the center console. Approaching it, he timidly reached out his hand and placed it on the controls. Gently, so as not to actually activate any of them. Just enough to feel the touch of them.

"Genius," Jimmy finally concluded his sentence. "But this… I couldn't have built this. I mean, I've built spaceships before, sure. But this … this TARDIS … this is beyond me."

Another batch of memories flooded Jimmy's mind. The Orange Day. Magic Kitten. What did they mean?

Jimmy gasped again, and his knees nearly buckled. Another thought occurred to him, orders of magnitude more terrifying than anything that had come before.

"When am I?" Jimmy wondered. His capacity for thought had just about fully returned, and he remembered that he was standing in a spaceship — though of course immensely more complex than anything he could have converted from Retroland rides. But more than that … it was a time machine. And if this machine was indeed of Jimmy's own design — though he didn't see how it could be — then, like so many of his other inventions, could something have gone wrong?

Jimmy turned from the console and ran for the exit door. He peered out the window, half expecting to see that the TARDIS was floating in deep space. But to his great relief, it seemed the TARDIS was safely parked in the backyard of his own familiar Retroville home.

Slowly, Jimmy opened the TARDIS door and took a single step onto the grass. Irrationally, he thought the whole world might explode if he had the audacity to show his face again on Earth after going off to travel Through Time and Space. But he took another three steps away from the TARDIS, and the planet indeed kept on turning.

"I'm home," Jimmy said, to no one in particular. He had no reason to suspect anyone would be around. There was nothing special about his arrival, and there had been nothing to announce his return.

But he was wrong.

"Jimmy?"

The voice was familiar but also somehow alien. Jimmy turned toward the sound and what he saw nearly caused his brain to seize up again.

It was Sheen. But yet, it wasn't. It was a grown man, at least 25 years old, but it looked like Sheen and spoke with Sheen's voice. And he wasn't alone. Flanking this grown-up version of Sheen was an equally aged facsimile of Carl.

"Is it really you?" the thing that looked like Carl asked.

"Of course it's me!" Jimmy replied. "But … is it really you? Carl, Sheen, you look … older."

"Well obviously," the older Sheen said, "That's what happens when time passes. Did you think we would still look like 11-year-olds?"

Jimmy was baffled, unable to comprehend how his friends had morphed into adults. Yet he was glad to see them, and in his relief he ran to embrace them. But as he drew closer he was assaulted by the most terrifying thought of the day.

Shouldn't they be taller?

If Carl and Sheen had spontaneously aged up, shouldn't they be taller than Jimmy? Yet he was looking them both directly in the eye. Stopping short, Jimmy looked down at the ground. It was too far away. Jimmy realized that he, himself, had grown taller.

Remembering that he had just exited a possibly-malfunctioning time machine, Jimmy asked, "Guys … what year is it?"

Sheen and Carl looked at Jimmy with a momentary look of amusement. But within a second, they realized Jimmy was in fact not joking. And their faces fell into a look of pained pity.

"Jimmy…" Carl began, "It's 2024. We haven't seen you in 15 years."

The world around Jimmy began to spin. Sheen bolted toward him and caught him just before he very nearly fainted.

"Where have you been?" Sheen asked, steadying Jimmy and keeping him upright.

"I … I have no idea. My memory seems like it's full of holes."

Then, after barely giving Jimmy a bit of time to recover from the last major revelation, Carl asked Jimmy a question that all but gave him a heart attack and a stroke at the same time.

"Well," Carl began, "Where's Timmy?"

"Timmy?" Jimmy repeated, at first unable to place the name. A second later, his eyes widened in abject mania. "Oh, God. Oh my God! Timmy!"

Jimmy instantly sprinted back to the TARDIS. He ripped the door open, leapt through the doorway, and slammed the door behind him. He bolted to the console, overwhelmed with the realization that Timmy was nowhere to be found, and with the intention of tracking him down. If he could only remember how these controls worked. He felt certain that he used to know, at one time. But now the buttons and switches looked up at him, set inside their panels, mocking him with their silence. Their stubborn refusal to give up the secrets of their function.

Jimmy grew more panicked, more frustrated, more distraught by the second. He had to find Timmy. He had to remember how to pilot this TARDIS. He had to…

"Think," Jimmy said, timidly at first, then with returning confidence, "Think … think … think!"

And with that, Jimmy's ability to think kicked back into high gear, and he had a—

"Brainblast!"

Instantaneously, the knowledge of how to fly the TARDIS flooded back into Jimmy's brain. With frenzied speed, he flipped switches, pushed buttons, spun wheels, and finally, defiantly, slammed down the lever that propelled the TARDIS into the time vortex.

Outside, Jimmy's thoroughly confused friends, who had just seen Jimmy reappear after a 15-year absence, watched as the TARDIS dematerialized right in front of them.

The TARDIS, now inside the vortex, zipped and sped and flew through the fabric of time itself, being pushed as fast as it could possibly go. The interior shook, and Jimmy struggled to stay upright. But he held fast to the control panel, pushing and nudging controls here and there, to keep the TARDIS on course.

Jimmy's thoughts were back now. Except that wasn't quite true. He only had one thought.

"I'm coming, Timmy. I'll find you. I'll find you!"

Jimmy Neutron

Timmy Turner

Through Time and Space

To Be Continued…