“See,” said Don, as he tapped on the screen, “I told you. Even if I prevent Velocivich from inventing the warp drive, someone else does it within a year, and we still colonize Tao Ceti before the end of the century. You can’t change history. History has a way with things.”

Behind the control panel of the temporal regulator, Rex sighed. He was two years younger than Don, but he’d finished a much more prestigious education program and he had trouble taking the word of his associate. “Fine,” he said, but he made sure to cringe just enough to show Don what a concession he was making. “This time, fine. Just fix it before the boss turns up.”

The overseer, who had spent the better part of a century studying the peculiar flow of temporality, wouldn’t have approved of his employees playing with the continuum to settle a bet. Last week, Rex had nearly lost his overtime pay, but he wasn’t going to let that happen again. Especially, especially not on the account of his arrogant, uneducated coworker.

“He left already,” said Don. “Besides, that’s the beauty of this. Even if we caused nuclear annihilation, we could just go back, tweak a few things, and set stuff the way it was before. No harm, no foul. As long as we stay inside the bubble, we can’t mess anything up in this universe.”

Again, Rex sighed. He was good at sighing. He twisted a knob and slid a lever upwards to correct his coworker’s perversion of the timeline, and Velocivich’s regulator coil resisted the overload. On their trans-temporal viewscreen, the warpsmall ship twisted into a whirl of blue and white as multiple dimensions compressed into one and the ship disappeared at a point halfway across the galaxy. History was safe for another shift.

“You don’t believe me?” Don demanded.

“Its just not good to mess with this stuff,” Rex said. “It’s not about the bubble. Time isn’t meant to move around like that.”

“A steak dinner says you’re wrong,” Don challenged. Rex sighed. If there was a sighing competition, he would win. “I’ll prove it. Watch. All life on Earth, bam. Gone in one swipe. I’ll fix it before the shift and no one will ever know.”

“It’s not about getting caught,” Rex repeated as he watched his coworker grab for the levers. “I mean, I’ve studied these things. I know how they work. It just isn’t the type of thing you should play around with.”

On the viewscreen, under Don’s control, the orbit of a small asteroid shifted nine centimeters to the left. It collided with another asteroid, then a comet, altering the comet’s trajectory nearly an entire degree. Rex drew in his breath sharply as the slab of ice and stone met a small planet to the left. The perfect marble of blue and green quickly shifted into swirls of dust and grey.

“Forward,” Don whispered as he turned another dial. The ball of water and soil cleared as millennia passed, and where blinking cities should have occupied the landmasses, relative darkness swept over the Earth. “Zoom,” Rex’s partner whispered, and the viewscreen obeyed. Waving blades of grass consumed thousands of pixels, giving way to two-story cottages and strange animal-driven carriages tumbling down cobblestone roads. On a huge field to the left of the communitys, a dozen small shapes kicked a ball across a manicured field of pristine green.

“What the…” Rex started, but the rest of the sentence was not yet complete in his mind. “Are you telling me…” he tried, but once again, the words failed. When the words failed, he sighed, and then he sighed again for good measure. “Fix it,” he said quickly. “Right now.”

“Steak dinner?” Don prodded. Rex nodded, barely thinking. He turned away from the viewscreen and shuddered.

“Ugh,” he said as he forced the image out of his mind. “Those goddamn monkeys make my scales crawl.”