RED SHADOW 赤影 (2001)

The secret warriors of feudal Japan were the ninja. Sent on impossible missions, the ninja were trained to work in shadows, gather information and defeat the enemy to build a world of peace. Akakage, Aokage, and Asuka are rookie ninjas under the tutelage of Shirokage. Their life is a series of perilous missions that entail intrigue, deception and intimidation.