Thousands of years into the future, mankind has colonized other planets across the galaxy and completely forgotten about Earth. On one part of the galaxy, the female space pirates and their colossal starship Sol Bianca get a surprise when a young girl named Mayo stows away on board the ship. The crew then embarks on a journey to Earth to find the whereabouts of Mayo's parents and discover the secrets of the lost planet.

Astro Boy appears to be a normal, playful kid, yet he is a robot capable of both flying and incredible strength. Living with his parents in a small town where humans and robots coexist, he has many friends thanks to his cheerful nature. Eager to learn and try new things, Astro and his companions often embark on exciting adventures. But their explorations are met with unexpected troubles when the wicked criminal Hamegg—joined by his accomplices Gora, a pink gorilla robot, and Professor Flau—interferes with their endeavors. As the little robot boy and his group bravely face challenges, their efforts become part of a journey to discover the world's values and wonders.

A sea otter and his friends, a raccoon and squirrel, live and play together in the forest.

The signing of a peace treaty has secured a tenuous ceasefire between mankind and the Zex, beings who emerged from space/time rifts connected to mysterious, distant worlds. Partnered with a Zex named Rigel, Azumi Kakamigahara must shoulder the fate of her own idyllic world. The unlikely pair head to newly established Fujimisaki Academy, where their destinies await.