Based on the stage adaptation of “Unico and the Kingdom of the Sun,” this animated film centers on a confrontation between the wizard Kukuruku and the gentle unicorn Unico. Kukuruku constructs a castle from dolls created by transforming men into building blocks. The plot focuses on the sorrow and terror experienced by the men who have been turned into dolls, and follows a girl named Cherry who hopes to restore the kindness within her brother, a student of Kukuruku. The film underscores Tezuka Osamu’s recurring theme that transformation involves not only physical change but also the inner heart of humanity.