The Change! (1986)

During the Heian Period, two babies, a boy and a girl, were born to different mothers in the powerful Udaijin family. The boy was a sickly child, and his superstitious mother was told by a priest that for him to live, he must be raised as a girl. On the other hand, the girl grew up to be a tomboy who liked to dress like a boy. Everything was going smoothly until Lord Kira (girl) started working at court and the emperor told Udaijin that he wanted Princess Kira (boy), who looks identical to beautiful Lord Kira, as his concubine. Now, Kira and Kira must switch places before all is too late.

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