Turn Back the Pendulum 11

Cornered by Urahara and Tessai, Aizen feigns innocence, claiming he merely stumbled onto wounded task-force members and tried to help. Urahara calls the lie for what it is, naming their condition as Hollowfication, which only earns Aizen's approval. When Aizen signals a retreat, Tessai looses a high-level Hadō, but Aizen brushes it aside with a chant-less Dankū barrier and escapes with Gin and Tōsen. As Hirako collapses, Tessai urges that the fallen be saved first and uses forbidden transport magic to whisk all of them, plus some Rukongai greenery, into the Twelfth Division headquarters. There Urahara confides that Hollowfication was one outcome of his research into strengthening souls, and that he devised a substance able to dissolve and rebuild the boundary between Hollow and Shinigami, a creation he names the Hōgyoku and intends to use to heal the eight.

Aizen deflects Urahara's accusations and blocks Tessai's attack with a wordless Dankū. The treacherous trio flee Soul Society. Tessai teleports the victims to the Twelfth Division using forbidden techniques. Urahara reveals the Hōgyoku and his plan to cure the Hollowfied Shinigami.

The second-to-last installment of the Turn Back the Pendulum flashback in Volume 37 (BEAUTY IS SO SOLITARY), this chapter traces the Hōgyoku's origin to Urahara's experiments. It is dramatized in Episode 212. Featured characters include Aizen, Gin, Tōsen, Urahara, Tessai, Hirako, and the future Visored.