At Ryuu"s birth, his people plan to offer him as a sacrifice to the Tyrannosaurus Shirano because of his dark skin. A monkey rescues him and adopts him as her own son, while Ryuu"s mother abandons the tribe to search for her child. The monkey, named Kiko, watches over him with fierce devotion.
Sixteen years later, Ryuu encounters Ran, a girl who was once sold to his original tribe. The tribe rejects Ryuu"s return and attempts another sacrifice, this time by burning him alive. Before the ritual completes, Shirano kills the tribe and Ryuu"s adoptive mother in a massacre. The bloodshed leaves Ryuu wounded but determined.
Ryuu then journeys with Ran to locate his mother and Ran"s brother, Don. Their path takes them through dangerous jungles and ancient ruins, seeking clues to their past.
Toei Animation Japan