A new dimensional space opened up between Soul Society and the real world. A special team of researchers were sent into it to investigate. However their communication got cut off.
In the meantime, Ichigo and Rukia are chasing a hollow in the park. After Ichigo successfully banish the hollow and did the soul burial to the girl ghost, Rukia got a message of strange reiatsu gathering activity nearby that she has never seen before.
Both of them went to the spot and met with the white ghost with red red pixie heads.
Rukia's communication to Soul Society got cut off. And all of sudden these white ghosts attacks Ichigo and Rukia. During the attack, another shinigami girl, appeared and banish the white ghosts with her Zanpakutou Mirokomaru.
As this new shinigami's have forgotten her background, Rukia went back to Soul Society to do some background check. Rukia leave Ichigo to keep a watch on her.
What's the new shinigami girl's name?
What were those white ghosts?
Why there is a new dimension in between Seoul Society and the real world?
All is revealed in Part 1 of The Bleach Movie - Memories Of Nobody above (wait for it to buffer).