An earthman boy, William, was extremely interested in space travels. He got two techniques from his father, Mighty, who was a world-famous physicist studying faster-than-light space travels and his mother, Sally, who was a biology professor at Columbia University. However, he was sometimes not so confident. This meant that he would rather not believe that he was actually very powerful. Due to this, Mighty and Sally decided to boost his confidence.

He set out and began his space travel, yet he came to another universe, which was surely unexpected! He had partners, including a female clone man, Ranran, whose prototype was William's physics teacher and head teacher; a fighter plane, Photon, who looked like a fighter plane in WWII; a racing car, Natalie Hurricane, who had crazy performances.

The party used an energy core to travel through a black hole and a five-dimensional space when they reached that universe, but unfortunately the energy core lost all the energy. So they had to go to all checkpoints on three planets to collect all energy, because only in this way could they go back to their universe.

Yet what would they encounter while they travel in this universe? Would they be able to go home?