The Soul Reapers find themselves in serious trouble when a mysterious individual known as Muramasa forces the zanpakutô of the 13 Court Guard Squads to take on human form and leads them in a rebellion against their former masters. With their powers weakened by the lack of zanpakutô, the Soul Reapers must now try to discover a way to stop Muramasa and defeat the manifestations of their own power without losing them for ever.
This first set of the twelfth season of the 'Bleach' anime contains the first twelve episodes (230 to 241) of the Zanpakutô Rebellion arc across two discs. This arc may be filler but it is still relatively entertaining as it contains some nice humour and some very good action. Most of the battles between the Soul Reapers and their zanpakutô are very good with Rukia's fight against Sode no Shirayuki, Toshiro's battle with Hyōrinmaru, and Rangiku and Momo's joint fight against Haineko and Tobiume being some of the best. Ichigo's battles against Zangetsu are also very good, especially when his Inner Hollow gets involved.
The plot of the arc is relatively interesting with a few nice twists here and there as the story goes along. There are a few minor issues here and there with the plot and I am unsure how recent revelations in the manga about the nature of certain zanpakutô could introduce a few plot holes for the arc but this is only a minor issue.
The character designs for the humanoid zanpakutô spirits are all very good but Sode no Shirayuki, Zabimaru and Kazeshini are probably my favourites. The anime also does a good job of making the interactions between the spirits themselves, as well as between the spirits and the Soul Reapers, entertaining with some very funny conversations here and there. The English dub is very good with all the zanpakutô spirits having very good voices, as does the main villain of the arc Muramasa (the Japanese is included as well of course for those who prefer it). The animation of the series remains good as well.
This was a good start to what is one of the more entertaining filler arcs of the 'Bleach' anime and I feel it is easily worth a full five stars.