Bleach the Movie: The DiamondDust Rebellion

A valuable artifact known as "King's Seal" is stolen by a mysterious group of people during transport in Soul Society. Hitsugaya Toushiro, the 10th division captain of Gotei 13, who is assigned to transport the seal fights the leader of the group and shortly after goes missing. After the incident, Seireitei declares Hitsugaya a traitor and orders the capture and execution of Hitsugaya. Kurosaki Ichigo refuses to believe this, and along with Matsumoto Rangiku, Kuchiki Rukia and Abarai Renji swear to uncover the real mastermind of the stolen seal, find Hitsugaya and clear his name. Meanwhile, a rogue Hitsugaya searches for the perpetrators and uncovers a dark secret regarding a long dead shinigami.

Synopsis from Anime News Network