Seventy years after the "Old World" was destroyed in a mysterious apocalypse, humanity survives in isolated underground shelters and scattered surface settlements known as the Ashlands. The world is plagued by "Heartless"—humans who have lost their minds—and mutated creatures, while "Awakened" individuals wield terrifying psychic powers at the cost of significant mental defects. Shang Jianyao, a resident of the subterranean megastructure Pangu Biology, joins the "Old Task Force" with a single goal: to find the cause of the Old World's destruction and save humanity from the Heartless disease. However, Shang Jianyao is not your average hero; he is eccentric, unpredictable, and potentially insane, often choosing to dance or offer "three favors for one price" in the middle of life-or-death battles. Alongside his team leader Jiang Baimian and their comrades, he traverses the wasteland to uncover the truth behind the 13 Kalendaria—the enigmatic deities that rule the months and the minds of the survivors.