Bleach the Movie - "The Dust Rebellion"

When an artifact known as the "King's Seal" is stolen during transport from Soul Society, Toshiro Hitsugaya goes to retrieve it. Hitsugaya goes missing after a battle with the thieves, leaving Seireitei to suspect him of treason. They order his immediate capture and execution. Unwilling to believe that he is capable of such a crime, Ichigo Kurosaki, Rukia Kuchiki, Rangiku Matsumoto, and Renji Abarai set out to find Hitsugaya and clear his name. Meanwhile, Hitsugaya is still searching for the thieves, and stumbles upon a dark secret involving a Soul Reaper long thought dead, a man named Kusaka Sojiro. He was a good friend and rival to Hitsugaya when they were younger.