Sakon and Ukon are brothers, who, through a unique kekkai genkai, share the same body, Ukon is the one on the back and is usually asleep, but wakes up if he is needed.
The Sound Four arrived in the Leaf Village to give a proposal to Sasuke. After a small skirmish Sasuke agreed but not before saying goodbye to Sakura. Sakon helped seal Sasuke in a transformation coffin.
During the escort the Sound Four ran into the Sasuke Retrieval Squad: Naruto, Shikamaru, Neji, Kiba, Akamaru, and Choji. Sakon went on ahead with Tayuya when Jirobo and Kidomaru decided to stay behind and fight. Kiba, Shikamaru, Akamaru, and Naruto caught up with them. Akamaru attacked Sakon only to get pulverized. Kiba tried to save him. At that moment, him, Akamaru, and Sakon got caught in an explosion and all three were blown into a canyon.
Following that Sakon then revealed he has a brother: Ukon, who inhabits his body. Sakon and Ukon both went into the second stage of the cursed seal. Kiba and Akamaru tried to defeat them, but failed. They tried a new attack called Man Beast Transformation Combo ,where they turned into a giant two-headed white wolf. Using Wolf Fang over Fang the wolf spiraled blindly, missing both times it was used. Sakon and Ukon then summon the Rashomon. Kiba and Akamaru used their final Wolf Fang over Fang to make a dent.Ukon and Sakon took this opportunity to try and get Akamaru and Kiba, but it didn't work when Akamaru threw acid on Sakon's face causing to go wash his face in the river. Ukon showed Kiba his and his brothers ability to meld into another's body, and then take it over through genetic and cellular manipulation. Wanting to kill Ukon then get his body taken over, Kiba struck himself with his kunai in a vital spot. Forcing Ukon out of the body. Kiba and Akamaru were in bad shape, and had to escape. They tried one last move and then fled into the river. Ukon and Sakon tracked Kiba and Akamaru to about a few miles down the river. Sakon had to rest in Ukon's body for the first time. Ukon was about to kill Kiba and Akamaru when Kankuro jumped in and used his puppets to save Kiba and Akamaru, and kill Sakon and Ukon.
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A Naruto OVA special
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