During a new visit to Vinea, Yoko returns to the Archangels' underwater city, drawn there by a mysterious probe and its damaged robot pilot, Myna. The latter is soon repaired, and immediately informs Yoko that the High Council of Vinea has decided to destroy the wandering space city of Kifa, as it threatens to crash into the planet. But Kifa is where Myna and her robotic people were exiled long ago. Yoko and her friend decide to help them …