A/N: Behold, the first prologue of my new crossover, Mobius. There will be four separate fics altogether, written from Itachi, Kisame, Sasori and Deidara's point of view. This will likely be the longest fic I have ever written, so feel free to cheer me on as I attempt to finish it. Assuming, of course, you like it.

This mostly takes place in the Games canon, although I have borrowed content from both the manga and the anime and messed around with the mythology a bit. Enjoy. Review. Tell me what you think. Where I went wrong. Inconsistencies you noticed. Things you liked. Et cetera.

Chapter One: Missing-no

Uchiha Itachi liked to understand what was going on around him. He was good at it. Perhaps too good. He sometimes mused that if he had been more ignorant of circumstances in Konoha he might never have been asked to do what he had done. But ignorance was dangerous. What he did not understand could kill him – Itachi used genjutsu enough to understand this. At least with the known you could see it coming.

Currently, he did not understand the creature hiding in the cave in front of him. Itachi stood beside a large rock outcropping, staring at the dark hole that passed, in these parts, for a cave mouth. He could almost see it, even through layers of stone. The chakra that pulsed faintly in the earth around them seemed to shy away from that spot, twisting unnaturally out of their usual straight pathways. Chakra lines in the earth. Those who couldn't see chakra didn't really believe they existed.

The creature they were avoiding, if one could call it a creature, didn't exist. Not in any way the Uchiha could comprehend. To normal eyes it was a silver mass, churning fitfully in place and fading in and out of focus. To his sharingan it was black; a deep, all-consuming blackness that seemed to both reject and consume the world around it. Itachi couldn't look at it for more than a half second at a time.

"It is not a demon." He said this more to himself than to the three resting behind him. They had come here assuming that it was. Surely nothing else could be the cause of so many mass disappearances, or such widespread interest. But demons were masses of concentrated chakra, burning with life and raw, unbridled power. This was not. This was…almost the opposite of that. What are you?

He heard Sasori sigh behind him, and felt him move to stand nearby. "It has to be something," the older man reasoned. Itachi wondered about that. Was it possible to be nothing? "Even the Kyuubi has weaknesses." That it did. "Is it made out of chakra?"

Of course. The others couldn't see it like Itachi could. He thought about the question. If this was the opposite of a demon, and a demon was made out of chakra… Could this be a different kind of chakra? He answered honestly. "I do not know." Then he tried to explain himself. How did one describe a ball of nothing? "It is as if… it does not exist."

He frowned. He didn't like being uncertain. This creature was interesting. It perhaps represented a part of the world never before examined. But it was also dangerous, and the longer Itachi stood staring at it the more convinced he became that they could not subdue it. And what would happen if they did, anyway? Their leader would try and use it to gain power over the countries. The Hidden Villages would try to stop him, and claim it for themselves. Wars would likely be fought over it. He heard Kisame speak behind him asking if they would go in again. Nothing ever changed, did it? And he would continue to be their loyal tool, fetching their powers sources for them.

The creature was moving. The chakra in the earth recoiled as it began to slowly move forward, resuming their usual positions behind it. Without thinking, Itachi took a step back. So it's going to take the fight to us. He signalled as much the others, using the short, efficient hand signs universal to all shinobi. He considered retreating. Coming back with reinforcements, perhaps. As if they would fare better against this than four of the strongest missing-nin in the Hidden Countries. No, better to fight.

He could see the creature now; tendrils of blackness curling into view. It would be in range soon. Then something changed. Suddenly the rock around the entrance crumbled. Itachi had to fight the urge to look away. It's speeding up. They couldn't fight it if it moved that fast. "No." He tried to run, but in the next second the air around him went black and Itachi suddenly felt very, very cold.

Perhaps the shinobi sent afterwards would be more careful when they didn't find his body.