High in the clouds above the Earth lies a mythological playground where the children of Greek gods and mythical creatures play. Among them is little Yios, a boy with a radiant sun for a head, which he inherited from his father, the god Helios. Whereas his father’s solar crown creates beautiful patterns, Yios’s radiance is uncontrollable. Its rays burst out in all directions, causing chaos on the playground, and so the other children avoid him. Yios tries his very best to make friends, but he cannot keep his explosive energy in check. The irritated children devise a malicious prank, causing Yios to fall from the clouds down to Earth. In this strange and unfamiliar environment, however, he meets a curious human boy. This unexpected encounter changes everything...