Bleach follows the adventures of the hotheaded teenager Ichigo Kurosaki, a teenager from Karakura Town who can see ghosts, a talent which lets him meet supernatural trespasser Rukia Kuchiki. Rukia is one of the Soul Reapers, soldiers trusted with ushering the souls of the dead from the World of the Living to the Soul Society —the afterlife realm from which she originates—and with fighting Hollows, monstrous lost souls who can harm both ghosts and humans. When she is severely wounded defending Ichigo from a Hollow she is pursuing, Rukia transfers her powers to Ichigo so that he may fight in her stead while she recovers her strength.
Rukia is thereby trapped in an ordinary human body, and must advise Ichigo as he balances the demands of his substitute Soul Reaper duties and attending high school. For aid in hunting the Hollows, the pair ally with a trio of other spiritually empowered teenagers: Ichigo's high school classmate Orihime Inoue, best friend Yasutora "Chad" Sado and the Quincy—humans who can fight Hollows—Uryū Ishida.
Eventually, Rukia is arrested by her Soul Reaper superiors and sentenced to death for the illegal act of transferring her powers into a human. Ichigo and friends enlist the help of ex-Soul Reaper scientist Kisuke Urahara, who also enables Ichigo to access his own Soul Reaper powers, to enter Soul Society and rescue Rukia. Shortly after the party's arrival in the Soul Society, conflict arises among the captains of 13 Court Squads when the captain of the fifth company, Sōsuke Aizen, is apparently murdered, which caused the Soul Reapers to begin fighting amongst themselves.
However, as Ichigo is almost succeeded in rescuing Rukia and Soul Society on the verge of civil war, Aizen reappears and reveals his intention to obtain the Hōgyoku —an orb of immense power—that Kisuke planted in Rukia's human vessel by faking his death and arranging Rukia's execution. Aizen is accompanied by his fellow conspirators, Gin Ichimaru and Kaname Tōsen who are the third and ninth company's captain, as they use Hollows to cover their escape into the Hollows' realm, Hueco Mundo . Afterward, Ichigo and Rukia reconciled with the Soul Reapers, who view the former as a powerful ally and designate him as an official substitute Soul Reaper.
Ichigo soon finds himself and his friends in escalating skirmishes with Aizen's army of humanoid Hollows, the Arrancar, as they are joined by the Vizards—Soul Reapers who were victims of Aizen's experiments in creating Soul Reaper/Hollow hybrids.
When one of the Espada—Aizen's 10 most powerful Arrancars—kidnaps Orihime, Ichigo and his allies enter Hueco Mundo to invade Aizen's palace. However, as Ichigo rescues Orihime, Aizen reveals her abduction was a distraction as he launch an attack on Karakura Town to sacrifice the souls of the living to create a key to the Soul King's Palace so he can kill the Soul King who reigns over the Soul Society.
When the Vizards join the remaining Soul Reapers to face their mutual enemy, Gin reveals his own agenda of assassinating Aizen. However, the latter then used the Hōgyoku to become a Hollow-like being and overpowered everyone. Ichigo ultimately succeeds in subduing Aizen at the cost of his powers and reverts to a normal human.
Renji has brown eyes and long crimson hair, which is usually kept in a high ponytail. As a child, Renji's hairline was leveled. Later, he styled it in a large widow's-peak.While out of uniform, Renji often wears a white kimono-like type of night clothing, with pink floral patterns on it, and a dark grey sash tied around his waist.
Hitsugaya is generally mature and serious, in contrast to his free-spirited lieutenant, Rangiku Matsumoto. Despite their personality differences, he and Rangiku seem very close. Tōshirō is easily annoyed by others goofing off or drawing unneeded attention to themselves, such as when he leads a team of Shinigami into Ichigo Kurosaki's school.
Byakuya Kuchiki is the 28th head of the Kuchiki Clan, one of the four great noble clans in Soul Society. He is also the captain of the 6th Division in the Gotei 13. His previous lieutenant was Ginjirō Shirogane and his current lieutenant is Renji Abarai.
Gin is a very mysterious man, since his almost constant smile and slitted eyes, combined with his heavy use of sarcasm and mocking politeness, make it very difficult to discern his thoughts. Many find his demeanor and appearance rather unsettling and there are very few who were willing to trust him even before he was revealed as a traitor.
Ulquiorra is a very cold, callous, and dispassionate figure, and is rather aloof, brooding, and indifferent, willing to harm both his comrades and enemies should they get in his way. He refers to anyone he does not find interesting as "trash", and treats them as expendable.