Eighty years ago, terrifying ancient beasts from the legendary Classic of Mountains and Seas suddenly awakened across the world, bringing humanity to the brink of extinction. With civilization collapsing around them, the remaining survivors escaped to a remote island and built a secluded virtual city known as A, hoping to find safety from the horrors beyond their walls. But their fragile peace comes with one strict rule: everyone must return indoors before the 10 PM curfew.As night falls, mysterious monsters begin appearing throughout the city, lurking in places where ordinary people cannot even perceive them. For most residents, the curfew is simply a matter of survival. However, young Lin Xiaoning soon discovers that he is connected to something far greater when the unusual birthmark on his face awakens a hidden power, allowing him to summon Beibei, a powerful steel mecha beast.Joined by Ling Xiao, a composed and exceptionally gifted companion, his childhood sweetheart Xiao Xiaoxiao, and other allies, Lin Xiaoning embarks on a dangerous journey into seven sealed locations. Each destination brings them closer to the truth behind the ancient monsters and the mysterious forces threatening their world.Yet the deeper they investigate, the more unsettling the revelations become. The nightly curfew is not merely a measure to protect the city’s residents—it conceals a secret that could change everything they believe about their sanctuary. As hidden dangers emerge and forgotten mysteries begin to unravel, Lin Xiaoning and his companions must uncover the truth before humanity’s last refuge becomes its greatest nightmare.