Set several years after the events of the original TwinBee, TwinBee and WinBee are relaxing at their island when they receive an SOS signal from the distant planet of Meru. The signal contains a message sent by Queen Melora, who pleads for the salvation of her planet from the invading forces of the evil alien Iva. TwinBee and his friends decides to set off to outer space to defeat the forces of Iva and save Planet Meru.