Every action anime series needs an archvillain. In the case of Tite Kubo's Bleach, that villain is the traitor captain, Sosuke Aizen. But what does his master plan look like, from start to finish?

Aizen took care to explain his schemes (and the reasons for them) to his friends and enemies alike, and he tried to justify his grand plan as him fulfilling a natural role that must be played in the universe. Put another way: there must be a supreme being at all times. Aizen grew convinced that such a being was absent, and he resolved to become that being himself and rule from the heavens for all time. The Soul King, who seemed completely passive and absent, did not satisfy Aizen's need for a "big brother" figure, so he elected to take on that role himself. And he was able to fool people by disguising this god complex in the shell of a seemingly mild-mannered man. Indeed, everything about his exterior was a deceptive lie, and characters like Momo Hinamori fell for it utterly.

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No one ever asked Aizen to do all this -- not even Captain-General Yamamoto or the members of Central 46 or the eccentric Captains of Squad 0. Aizen is a highly ambitious and power-hungry individual, and he decided all on his own that 1) a supreme being must exist, and 2) he alone was fit to become that being.

Aizen's Secret Research

Aizen started work on his grand plan many years before Ichigo was born in the shadowy corners of the Soul Society. He is a proficient researcher, and he turned his studies toward a bizarre topic: trying to break down the barrier between hollows and Soul Reapers. Common wisdom held that these two races are forever distinct and destined to fight, but a young Sosuke Aizen felt differently. He was determined to lend hollow powers to Soul Reapers, and help hollows break off their masks and gain Soul Reaper powers. These hybrids were the key to ultimate power, or so he believed, and so he created a mystic little sphere called the Hogyoku.

Although Aizen presented this sphere to many Souls and Soul Reapers, the Hogyoku was incomplete, and repeatedly failed to bring Aizen the desired results. Meanwhile, Kisuke Urahara launched this research on his own and he, too, invented a Hogyoku -- one that was even more effective than Aizen's.

Some 110 years before the main events of Bleach, Sosuke Aizen had been appointed the Lieutenant of Squad 5 under Captain Shinji Hirako, and Shinji put him there to monitor him more easily. Aizen was one step ahead, however; he used his shikai's hypnotic power to put a proxy in his place, giving him leave to continue using the Hogyoku. Aizen started turning hollows into Arrancars, though none of them were powerful enough for his needs, so he turned to Soul Reapers.

Fast-forward nine years, and Aizen and his minions, Kaname Tosen and Gin Ichimaru, lured out Squad 9 and some other Soul Reapers to a remote area during a crisis. Aizen pounced and forced the assembled Captains and Lieutenants to develop hollow masks and undergo hollowfication. Shinji, Hiyori, Kensei, Lisa and the others were helpless to stop it, though when Kisuke Urahara and Tessai both stepped onto the scene, Aizen fled. Kisuke couldn't undo the hollowfication but did he help stabilize the victims.

Unfortunately for Kisuke, he took the blame for that incident, and Central 46 banished him to the world of the living in Karakura Town while Aizen went free. This left Aizen free to create mutant hollows such as Metastacia and White, but when these too fell short of what he needed, he decided to go after Kisuke's Hogyoku next.

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Rukia Is The Key

Much later, Aizen arranged nearly every event in Ichigo's life to make sure that he could get his hands on the Hogyoku and steal it from Rukia's body. Kisuke hid his Hogyoku in Rukia's gigai body and altered that gigai so that it would slowly turn human, and thus make Rukia nearly impossible to find. But it was too late: Aizen was already privy to this plan, and made sure that Rukia would end up stationed in Karakura Town and perform the crime of giving her Soul Reaper powers to a human (Ichigo).

This led to Rukia's arrest and incarceration in the Soul Society and, by now, Aizen had already slaughtered every member of Central 46. He created illusory doubles of them and through them, had Rukia's execution date moved and made sure that she would be destroyed in soul-destroying flames on the Sokyoku Hill execution site. He sowed discord among the Captains, then faked his own death and left a good-bye note for Momo (by now his Lieutenant).

Aizen continued to mislead the Soul Reapers, including turning Momo, Hitsugaya and Gin against each other. Only Toshiro realized that a plan was afoot. The young Captain, accompanied by his Lieutenant, discovered the slaughtered remains of Central 46, but he was too late to do stop Aizen's plans. The execution began as scheduled, but Ichigo's arrival, and the civil war among the Captains, spared Rukia a fiery death. Ichigo fought Captain Kuchiki and won, and proceeded to rescue Rukia.

Aizen stepped onto the scene with Gin and Tosen, and easily overwhelmed everyone who got in his way. He then used a mysterious device (courtesy of Kisuke) to extract the Hogyoku in Rukia's body without killing her, and the three traitor Captains fled when Menos Grande arrived. But the worst was yet to come.

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Hollow Power

Tier Halibel looking down seriously in Bleach.

The three traitor Captains established the hollow world of Hueco Mundo as their base of operations, but this was the means to an end. Sosuke Aizen melded the two Hogyoku into a single sphere, and forcibly accelerated the development of very powerful Arrancars, making an army. But he didn't plan on wiping out the Soul Society with this battalion -- he just needed to keep the Captains busy so he could reach the Soul King's palace and become the true god of all creation. To do that, he needed to make a key called the Oken. Creating the Oken is tricky, but Aizen knew the schematics.

Aizen ordered Ulquiorra, one of his top Arrancars, to kidnap Orihime and prompt Ichigo to storm Hueco Mundo and rescue her. Four Soul Reaper Captains backed him up to fight the Espadas, which left fewer fighters available to defend Karakura Town once Aizen arrived there to launch his plan. Although the Soul Reapers created a proxy Karakura Town to minimize collateral damage, Aizen proceeded as planned, and very nearly succeeded until the Visoreds (his previous victims), Isshin and Kisuke provided reinforcements.

By now, Aizen had infused the Hogyoku into his body, and this sphere can manifest its user's desires into reality. Aizen morphed again and again until Kisuke and Ichigo cornered him and trapped him with kido. Aizen protested loudly, not just because he was beaten, but because he earnestly believed that his mission was critical to the universe and only a man like him could set things right. Aizen calmed down later, though, when he was sentenced to 18,800 years in the Muken prison. He openly mocked the new Central 46 members for passing judgment on a supposedly superior being like him. So, they extended his sentence to 20,000 years and had his mouth covered, too.

The Grand Conclusion

Is there a lesson to be learned from all this? No one saw Aizen's plan coming and he would have succeeded if it weren't for Ichigo's surprise rise to power and Kisuke's need to set things right with his longtime enemy. Aizen hatched his scheme to rule all of creation, spurred on by an emotion that Bleach often explores: despair. Even Soul Reapers and hollows face despair when their noble causes are revealed to be lies, or when they can't find a reason to fight on or if their loved ones are lost. Ryuken Ishida felt despair about the future of the Quincy; Byakuya faced despair when he lost his wife Hisana (and hardened his heart) and nearly all the hollows felt despair about their meaningless existence and hunger. Nnoitora Gilga pointed out that there is no redemption for hollows, and not even Aizen can change that fact.

Aizen, for his part, despaired that there was no ultimate being to guide the universe with a benevolent hand. He was almost like a frightened child without a parent, and he sought to overcome this despair by becoming that being himself. But this was the ultimate illusion: there was no actual need for such a being at all. In Bleach's final chapter, the Soul Society and Karakura Town alike are doing well in the newfound peace after the Wandenreich is defeated, no ruler from the heavens needed. For all his power and brilliance, Aizen didn't realize that the true meaning of life is what you decide for yourself, not what a supreme heavenly ruler tells you. By the end of Bleach, he had figured out some of this -- claiming that courage in the face of uncertainty and peril is what makes life worth living.

Sosuke Aizen found peace with the will of the universe at last... while securely ensconced in the ultimate prison.

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