Many years ago earth was nothing like now, it was so bad, way behind your imagination. would you want to go there- probably not, you could get killed after all. but Kim ChangMin, Kim MinJun, and Kim MyungHee are assigned to go there by their master. they need to go and rescue everyone before Earth is destroyed, but it will be hard since the people are in Earth. They might even not make it alive, and if they will, what will they do with all the people?