Jiang Che, a transmigrator, arrives in a post-apocalyptic world where monsters and demons have resurged. On the brink of death, he activates the Classic of Mountains and Seas System, unlocking the powers of mythical beasts such as Bifang and Zhu Yan. He goes on to slay the Yellow-Skinned Demon and the Red-Clothed Evil Spirit, and unexpectedly subdues the Dark Gold Divine Artifact, the Ghostly Netherfire Gourd. After unraveling the mystery of Lotus Mountain Manor, he exposes a conspiracy by an organization from the Spirit Realm to use the Nine Key Envoys to activate the First Seal. Joining forces with the Paranormal Management Bureau, Jiang Che destroys numerous formation nodes before venturing deep into an air-raid shelter to confront the ultimate seal and shoulder the responsibility of protecting the entire city against the Spirit Realm.