Source: AniDB.net/Wikipedia.org
Bleach: Fade to Black, I Call Your Name is the third animated film adaptation of the anime and manga series Bleach. Directed by Noriyuki Abe, the film was released December 13, 2008.
The movie opens with Mayuri Kurotsuchi, in his laboratory, being attacked by a mysterious scythe wielder, somehow causing him to lose his memory. After his lieutenant, Nemu Kurotsuchi, arrives to find out what the disturbance is, he begins to panic, having no memory of her.
He proceeds to destroy a control panel, triggering a massive explosion of reiatsu that covers all of Seireitei in a cocoon-like substance that spawns reiatsu snakes. Kenpachi Zaraki hurries only to witness the disaster and becomes imprisoned in the reiatsu. The explosion destroys Seireitei and induces amnesia in all the Soul Reapers residing there.