Princess Ayeka from the planet Jurai, seeking her long-lost half-brother Yosho, arrives on Earth. However, when she finds Ryoko, who she believes is responsible for Yosho's disappearance, she imprisons her and Tenchi aboard her ship. Luckily, Ayeka's little sister Sasami helps them to escape, and Ryoko uses her own spacecraft, named Ryo-Ohki, to crash Ayeka's ship and strand the princesses on Earth.