By sheer fate, Ishida unexpectedly meets a girl named Rhina. Together, they set out in search of a lost city at sea and its myriad treasures that are regarded by most people as legends. Ishida’s father had set out in search of the place, too, but never returned. The journey will take the bold travelers onto mysterious islands, through sun-scorched deserts, and over perilous mountains. But most importantly, the two travelers will discover their true selves when they confront what will determine their fate. The questions remain: will they be able to find the lost sea city and Ishida’s father? Or is the place they are searching for simply non-existent?