What Happens in Naruto Movie 3?

Answer 1

A enemy trys to inplant special ability´s from members of different clans.

So the enemy wants kakashi´s sharingan.

When kakashi was young that enemy (forgot his name)

used a jutsu on kakashi so he could control kakashi.

So kakashi left the village to go to the enemy.

And tsunade (5TH hokage putted a bomb spell on kakashi.

So it was just a sacrifice for the village.

And naruto ofcourse, cant let this happen