Seeking the elusive heart plasma to save his homeland, Go-chan lands on Earth, where he befriends Moko, a farm girl living with her grandfather and the mystical Chinjuumin creatures. As they share joyful moments, a crisis unfolds as humans intrude on the Chinjuumin's forest sanctuary. Amidst this chaos, Moko's peaceful life takes a turn as her city-dwelling grandmother makes an unexpected appearance.