In 2219 AD, the resources of the Milky Way were exhausted, and humans successfully entered a brand new galaxy: the Kalan Galaxy. The Kalan Galaxy emits a special kind of cosmic ray, which mutates the cells of most animals and some plants. The cell nuclei can produce a releasable energy. Human beings who enter this galaxy mutate one after another within a few days. Due to energy exhaustion, the spacecraft lands in the Kalan Galaxy, a beautiful blue planet that is very similar to our home planet, the Earth.