Kakuzu is missing-nin from the Hidden Waterfall Village who has the ability to use five elemental affinities. His body is covered with stitches because of the Earth Grudge Fear jutsu that allows him to separate his limbs at will as well as steal organs from others to extend his own life. Kakuzu can hold up to five hearts in his body at one time making him extremely hard to kill. He is a short tempered individual as well as greedy, his main concern in life is profit, he refers to himself as Akatsuki's treasurer.
Kakuzu uses the Earth Grudge Fear jutsu which is composed of thousands of dark threads inside his body to perform long range attacks by extending his body or detaching his limbs. He can also use this jutsu to mend wounds to himself or others. Kakuzu stores the hearts he steals in masks located on his back giving him massive amounts of chakra. He can detach those masks and create a body for them made up of the threads inside his own body. Kakuzu can have the masks attack separately depending on what nature type that heart is or combine the masks with his own body to increase his fighting power. The Earth Grudge Fear jutsu is a unique jutsu that he stole from the Hidden Waterfall Village when he escaped from imprisonment and killed the village elders. Along with those abilities he is surprisingly skilled in taijutsu and is able turn his skin rock hard for both defensive and offensive purposes.
Kakuzu's partner in Akatsuki is Hidan, a nearly immortal individual who cannot be killed. Kakuzu's violent temper led to the deaths of his previous partners and caused his pairing with Hidan. Kakuzu and Hidan were ordered to capture the Two-tails jinchuuriki Yugito Nii, which they did. Upon doing so they were then ordered to capture the Nine-tails jinchuuriki Uzumaki Naruto and set out to the Land of Fire. During their search they came upon a temple that had a monk named Chiriku residing in it. He was listed in the Bingo book and caught Kakuzu's attention. The two killed Chiriku and every other monk in the temple leaving only one survivor unknown to them. This made the Hidden Leaf aware of their presence, Tsunade sent twenty squads of four out to capture or kill them. This led to the team of Asuma, Shikamaru, Izumo and Kotetsu setting up an ambush for Kakuzu and Hidan at a collection station for bounties in the Bingo book. Kakuzu detained Shikamaru, Izumo and Kotetsu while Hidan killed Asuma, they were summoned by the Akatsuki leader to seal the Two-tails when Leaf reinforcements arrived. Three days later after sealing the Two-tails, Kakuzu and Hidan continued their search for Uzumaki Naruto. They were tracked down by Kakashi, Shikamaru, Chouji and Ino. Kakuzu was defeated when Naruto, Yamato, Sakura and Sai showed up. He was dealt a mortal wound by Naruto's Rasen-shuriken and then later executed by Kakashi using his Chidori.