When a mysterious fog descends upon the city of Hongkuang, it quickly becomes clear that this has nothing to do with pollution, but rather with a gigantic quarry that exploded years ago. A mysterious being slumbered in its depths, and now it awakens. Only the infamous Bureau 749, a government agency specializing in supernatural phenomena, is equipped to stop this threat. Young Ma Shan and his friends have been trained for this emergency. But their superhuman abilities come at a high price...