This is the first movie in the series, and what considered as the start of three full-length episodes where substitute Soul Reaper, Ichigo Kurosaki has to help his friends in certain cases that come up.
Normally it involves Hollows, but in this case Ichigo comes in touch with a strange girl called Senna who looks like a Soul Reaper, but on seeing her, Ichigo realizes that there is an influx of Blanks. These are already passed over souls who have no memories and they are aimlessly wandering around causing trouble. They are on their trail, but have no idea why it happened and who the ringleader is. Ichigo only remembers that Kon has seen a dark figure hanging around the Blanks. He doesn’t have to wait long, though as Senna is captured and held by The Dark Ones, a faction who are out to cause trouble wherever they go.