 Founded in 1962, Tatsunoko Production celebrated their 40th year of animated film production by releasing Karas in 2005, their first production being Space Ace in 1965. Keiichi Sato joined the company as the project director after he pitched its concept of a life-sized dark hero to the management. He researched production and direction techniques from kabuki, a form of traditional Japanese theater; and Japanese staged sword fights as materials for the project. Choreographed sword fights rendered with 3D animation were rare at that time, and Sato felt this would help distinguish the show. The use of theatrical elements and movie shooting techniques in its presentation sets Karas apart from its contemporaries. Producer Kenji Nakamura felt the team's lack of experience in this area pushed them to ignore their previous animation work experience and break free of restrictions influenced by traditional animation production.
