McKay climbed silently into the back of the car. His parents were still arguing as they shut their doors and his father started the engine. McKay stared out of the window, his mind working fast. He thought back to the time just after the science project. He could not actually remember the science fair itself. He could now work out why. But what had happened in the science fair? Had his project actually been entered? That had been what he'd assumed for the past quarter century or so. But now he was not so sure.

He was startled to find out they were already at home. As he climbed out of the car, not bothering to pick up his schoolbag, his father ordered him to his bedroom. McKay shrugged. It wasn't as though he had anywhere else to go.

When he reached his room, he could still hear his parents' angry voices downstairs. He found himself falling back into old habits, as he headed for the bookshelf, spent a few minutes choosing a book, then lay on the bed and fell deep into the world the book offered him.

Zelenka consulted his computer, then turned back to the others. "I've taken some more readings, and sampled the frequency of the tone given by the control," he announced. "It's very slight, but there has been a definite change in tone over the past hour or so. It appears Rodney is right." He shrugged, while Rodney looked smug. "It appears all we have to do is wait. I suppose it makes sense. This transference is self-limiting. Eventually the situation should reverse itself and return to normal without our interference. I believe it should happen within the next couple of hours, if the change in pitch does indicate the return to stability."

"Well that's a relief," said John. Then he caught sight of Rodney's face and grinned. "Not that we don't like having you around, Rodney, but it's kind of weird, and we really need our chief scientist back here."

Rodney nodded. "It's been kind of fun," he admitted. "After all, not many kids get to see their future. Of course, time travel is theoretically possible…"

John held up his hand as Rodney launched into a scientific explanation of the theory of time travel. "What say we have some fun while you're still here?" he offered.

Rodney looked at him suspiciously. "What do you have in mind?"

John smiled sweetly. "Fancy a game of chess?"

McKay, deep into his book, began to feel sleepy. The late night the night before was starting to catch up on him, and the words in the science book he was reading began to have its usual calming effect on him. Before he realised it, the book slipped off the bed and he lay sleeping peacefully, one arm hanging off the side of the bed.
John grinned and tapped his fingers on the desk confidently. It was cheating slightly, to play Rodney at chess while he was still only twelve years old, but hey, when would he have this sort of opportunity again? He'd been desperate to try his hand against McKay for ages, since he'd first overheard him complaining about not getting challenging partners to play against. But never having seen him at a chessboard, he couldn't help sneaking in this chance to find out just how good he was.

"Your turn," he prompted.

Rodney stared down at the board. John's grin widened. He nearly had him. Okay, he was beating a twelve year old Rodney, but it was a start. Now he had an idea of his strengths and weaknesses, he might even try challenging McKay as an adult. As long as he came back okay…

Even as he had this thought, he looked up to see Rodney's eyes drifting shut. "Hey, what's up?" he asked in alarm, as Rodney slowly slipped sideways off the chair.

"Rodney! You get down these stairs right now!"

Rodney jumped up in alarm. He found himself half on the bed, half on the floor, with an open book next to him. He didn't remember a book; he had a vague feeling that he'd been doing something to do with chess. But he couldn't remember clearly. What a strange dream!

"Rodney!" His father threw the bedroom door open. "Get down those stairs now. There's someone to talk to you."

Rodney shook his head, feeling dizzy. What was going on? The last thing he could remember clearly was his music lesson. But somehow the pain of the memory didn't feel as strong as he'd expected. It felt as though it had happened a long time ago. He looked down at the book. Brighter than a Thousand Suns: a Personal History of the Atomic Scientists. He'd been reading it between sessions on his science project – which was now missing from the corner of the room. Had his father taken it away as he'd threatened?

"Now, Rodney," his father insisted. He seemed strangely agitated. Rodney turned from the book and walked down the stairs and into the living room. Two men in suits were sitting on the couch. "Hello, Rodney," said the older of them. "We're from the CIA. We just want to talk to you about your school science project."

McKay felt dizzy. He found himself lying on the floor, with Colonel Sheppard bending over him looking concerned, and hastily pulled himself onto the nearby chair. "I'm sorry," he said, shaking his head as if to clear it. "I just came over all dizzy for a moment." He stared down at the chessboard, trying to figure out what had happened. He had a vague memory of exploring the city, but could not remember anything else. He put his hand up to his head, and found a bandaid on it.

"You banged your head on some equipment, remember?" said Sheppard, watching him closely.

"Ah, yes," McKay said. He supposed he must have a touch of concussion. He looked at the chessboard. "We were playing chess?"

"Ah…" Sheppard seemed strangely uneasy. "That's okay, we don't have to…"

"No, no, no, that's okay," McKay reassured him. "I'm okay now. I just felt a bit strange. But I'm okay."

He reached out and picked up a knight. Sheppard seemed to relax slightly. McKay frowned, studied the board, then placed his knight decisively back on the board. "Checkmate, I do believe," he said.

Sheppard glared at the chessboard as if it had done him a personal injury.

And we're done except for an epilogue, I guess! Hope you've enjoyed the story, and thanks for all the reviews.