A/N: Peri's comments regarding Americans are her own, and do not represent the views of this half-American author, Big Finish, or the BBC. This is also probably a good time to mention that I don't own Doctor Who or any of the characters presented in this fanfiction. If you haven't yet had the pleasure of encountering Erimem, I recommend you seek out her debut in Eye of the Scorpion.
[In the life of the Doctor there are good days, and there are bad days. Sometimes, when he's feeling down, the TARDIS (who has a very long memory), takes over the viewscreen and reminds him of the good days.]
The TARDIS library had very few spaces of wall that weren't covered in books, and most of them held programmable false windows for reading by any weather. It was a massive room, with row upon row of every media and genre ever created. In one of the open spaces, a man and a woman sat on opposite sides of a small round table. Hovering over it was a large, transparent sphere, marked and grooved in a complex pattern. A number of coloured lights surrounded it, each moving on different orbits.
"What about switching that blue one-the one that just turned green- with the red one there?" the girl asked, pushing her short-cropped hair out of her face.
"No, that would trap the yellow one there, see?" the fresh-faced man said, pointing to another of the lights moving lazily in low orbit around the sphere.
"Well, how about this, then?" The girl stood and poked her finger into a bead of white light, which ceased moving, its tiny glow illuminating her dark complexion. Carefully, she pulled the light downward into the path of a blue light, which turned violet, increased speed, and slid sideways into a different orbit.
"Nicely done, Erimem," the man said, fetching a pair of spectacles from inside his white coat. Donning the glasses, he inspected the surface of the sphere. "Yes, that's definitely a step in the right direction. Now, if I do this…" He plucked at a large bead of light that matched his blonde hair and moved it up towards the path of a green light, which shuddered, slowed, and sunk directly into the path of a high speed blue. The two lights collided, and the surface of the sphere rippled. "Oh. Sorry."
"That's alright, Doctor," the girl laughed, catching the wildly ricocheting blue bead before it could do any further damage. The surface of the ball solidified its etched pattern even more complex. "You didn't see the green light, it was an easy mistake. All the same, this is quite tricky."
"It is rather, isn't it?" the Doctor agreed, polishing the leafy stalk of celery pinned to his lapel. "Though you should see the Expert level ones they have on Gallifrey. Some of them have smaller, orbiting spheres."
At that moment, a rather buxom girl entered the library, yawning. She noticed the others and headed for them. "Well, good morning, you two," she said, her distinctly American accent and otherwise chirpy tone holding just a hint of annoyance. "Nice of you to let me know where to find you."
"Ah. Well, we didn't wish to disturb you, Peri," the Doctor said placidly. "We knew you'd find us eventually."
"Oh, yeah? You never let me go off on my own outside the TARDIS," Peri pointed out.
"Yet you seem to be so good at doing it anyway," Erimem observed, eliciting a chuckle from both Peri and the Doctor.
"Why, Erimem, I do believe you are getting the hang of sarcasm nicely," Peri said. She looked up. "What are you two doing, anyway?"
"It's a Time Lord logic puzzle," the Doctor explained. "Each of the little colored lights is on a different temporal orbit, but they affect each other just the way moons and planets do. The beads change colour when they're in specific orbits. The goal is to get all the lights the right colour, speed, and orbit."
"But whenever you move one," Erimem added, "it affects the others in unpredictable ways. It's very tricky."
"Oh, I get it!" Peri said. "It's a Rubik's Cube!"
"Essentially, yes," the Doctor nodded. "A fifth-dimensional space simulation Rubik's cube."
Erimem looked confused. "What is a Rubix?" she asked.
As the Doctor explained the simpler modern earth puzzle to Erimem, Peri noticed a hammer sitting on another table nearby. "What's this doing here, Doctor?" She picked the hammer up. "Have you been adding more shelves or something?"
"Oh, that old thing?" the Doctor said, looking over. "It's a shockwave hammer. Useless for putting up shelves, but pretty handy for getting through walls. I wondered where that had gotten to."
Peri studied the puzzle. "How long have you been at this?" she asked.
"Only an hour or so today," the Doctor replied, "but I haven't solved one for the past hundred years or so."
"Well, then." Peri smiled. "Why don't we try the American approach?"
"What would that be?" the Doctor asked.
Peri swung the hammer and connected solidly with the floating sphere. The vibrations caused the surface of the sphere to blur and ripple immensely, as around it, the lights went mad, bouncing off one another in all directions. Eventually, they settled down and, to the amazement of all, the sphere's surface smoothed out completely blank.
"How on Gallifrey did you do that?" the Doctor said, stunned.
"When these kinds of puzzles get old, they start to wear out along the edges. Pieces click into the places they've been in the most. So introduce some randomness and it may well just solve itself, with a bit of luck."
"So, that's the American approach?" Erimem asked. "Hit it with a hammer?"
"Unfortunately, yes," the Doctor said. "You'd be surprised how many situations those people will try to solve with "hit something with a large stick.""
"Well, actually," Peri said, "the American approach is, if you can't win, cheat!" Everyone laughed.
"You know, I think I've got an old space-chess set around here somewhere," the Doctor said, deactivating the sphere. "What do you say, me against you two? The rules aren't all different to normal chess."
"What is this 'chest?'" Erimem asked. There was a pause as Peri explained the basic premise of chess.
"Ha! It's a war game!" Erimem laughed when Peri had finished. "I, Erimem-ushin-teperem, former pharaoh of Egypt, accept your challenge. You think you can beat the two of us on a war game? You're on, Time Lord!"