About this story:

This is AU, take off from canon, during the Battle City arc.

Eventual yaoi, Yami Yugi/Atem x Seto/Set, some hints of other pairings.

The usual disclaimers apply.

1. Prologue

Mokuba pulled off the wrapping paper and looked at the box inside. There was a picture of a large, shining dragon with a knight in silver armor seated on it as though it was a horse.

"It's a puzzle."

"A puzzle?"

"The idea is to put all the pieces together, and then you see the picture, Mokuba. It's fun, you'll see."

Mokuba looked the box over, unsure, and scrutinized his brother's face.

"I'll help."

Mokuba dropped the box and threw his arms around his brother's neck. He didn't care whether he liked the activity itself or not. If it meant his brother spending time with him, he was all for it. "Thanks, Nii-sama!"

"You're welcome." Seto smiled warmly, his dark eyes shining. "Shall we start now? Father won't mind if we use the large table."

"Are you sure he won't mind?"

Seto just smiled and took out his pocket knife to cut the seal on the box. "This is a jigsaw puzzle," he explained. "All you have to do is put the pieces together to match the picture on the box. But there are more complex puzzles that form three-dimensional objects, or ciphers, or combinations of things …" His eyes became distant and dreamy as he considered the possibilities.

"Nii-sama?"

"Oh, sorry! I was just thinking about things I'd like to do. Let's get started. Why don't you go through all the pieces and find the ones with straight edges? When we find them all we can start looking for ones that fit together. Meanwhile, let's separate the ones that are the same color into piles."

Mokuba started sorting through the pieces. Then he picked up a piece and said, "What about this piece, Nii-sama?"

Seto looked at the fragment of yellow-gold, then at the box.

"Hn. This piece doesn't even belong in this puzzle. The company must have packed it in the box by mistake."

"That's weird." Mokuba took the piece back from Seto and fingered it staring at it curiously. "I wonder what picture it's part of?"

"We'll probably never know," Seto said. "Some mysteries are virtually impossible to solve. When you don't have the key … or all the pieces …"

"Even for you?" Mokuba looked at Seto incredulously. He thought Seto could figure anything out.

Seto smiled and ruffled Mokuba's hair. "If there's not enough information, not even I can figure it out, Mokuba. Some mysteries are just … mysteries."

Author's notes:

The start of another story. I hope that you'll enjoy this one.

You might notice that this first little part has nothing and everything to do with the story. I hope you'll see what I mean.

I have written most of the skeleton of this story and just have parts to fill in and polish ... still, it might be a couple of weeks before the story really gets started with chapter 2. Please forgive me for being anxious to start and posting the first chapter. I am finishing up my latest 5D's story which is almost finished and then I'll be able to turn my full attention to working on this one. :)

A preview of chapter 2:

Mai strode up to Mokuba. "What is the meaning of this?∙! We can't even conclude our duels?∙! I was about to crush this dude!"

Mokuba spun on her. "Whoever is behind Nii—Seto's disappearance might be dueling right now. To prevent this person from benefiting from their plot, I have to stop all duels immediately. I'm sorry, Mai, I can't make any exceptions. And you, don't even start. I don't want to hear it. You don't even like my brother. He might be in trouble, so don't complain about your selfish needs!" Mokuba couldn't help it. He let it all spill out on Jonouchi, whose angry face appeared over Mai's shoulder.

The story starts in earnest.