More than ten thousand years ago an alien race landed on the planet Haixing, some among them fused their cells with plants and animals, forming the Yashou tribe. Some stayed deep under the ground and were called the Dixing people. Their cells mutated as well and they became capable of some supernatural powers. There was, however, peace between the three tribes. Until a meteor hit Haixing and the Dixing's resources started to deplete and they escaped to the surface and started a war with the Haixing and the Yashou people. Zhao Yun Lan, a human, falls into a deep slumber to save Shen Wei, a powerful mutant. In return, Shen Wei fulfills his promise to Zhao Yun Lan to be the keeper of the boundary. The Haixing, in the end, won the war after they created 4 Holy Tools out of the meteor. The three tribes then agreed on a peace.
The humans create the Special Investigation Division (SID) to catch mutants who escape exile and bring them back to the border. After a million years, both sides were able to live peacefully and the SID became irrelevant and forgotten altogether, that is until a series of weird events begin to occur. Shen Wei, now as a gentle and calm university professor, joins the SID and realizes that Zhao Yun Lan is awake and knows nothing about their past. The SID also comes to realize that Shen Wei is no ordinary professor and somehow linked to the mysterious "four sages".