Shadow(2004)

Shadow is a Japanese anime series set during the final days of the Shogunate period, when ninja assassins operate in the shadows to survive. Karyuu, a skilled female shinobi, accepts a contract to eliminate a target—only to discover another assassin, Uzume, has been hired for the same job. What begins as a tense confrontation between the two women escalates into an intense rivalry as they navigate a dangerous world where loyalty, survival, and competing missions collide. The series blends period action with the cat-and-mouse dynamics of two formidable fighters caught on opposing sides of deadly contracts.