During the Lantern Festival of the Tang Dynasty, Chang’an is thrown into chaos when a towering lantern structure, standing a hundred feet tall, suddenly explodes, sending an illusionist plunging to his death. While investigating the mysterious incident, official Shen Zhaoying discovers an unusual companion—a chubby, short-legged golden tabby cat carrying a bloodstained copper bell. Most people believe the animal is a dangerous cat demon, but the truth is far more complicated. The cat has only one purpose: to reclaim the bell, which bears three engraved characters—Shen Buyi, the name of Shen Zhaoying’s father, who vanished without a trace ten years earlier.With the mysterious cat now tied to her father’s disappearance, Shen Zhaoying has no choice but to embark on an unexpected journey alongside her stubborn feline companion. Their investigation leads them through a bizarre world of mechanical lanterns, enchanted mirror palaces, underground cities inhabited by cats, and twelve mysterious town lanterns. As a series of strange supernatural cases unfolds across Chang’an, they begin uncovering a sinister conspiracy connected to the secretive Myriad Illusions Workshop.But the deeper Shen Zhaoying digs, the more she realizes that these mysteries are connected to a tragedy from ten years ago—a hidden secret involving her missing father and the enigmatic cat king, Jinbing. Determined to uncover the truth, she sets out to find her father with a knife in hand, while Jinbing faithfully carries the copper bell, determined to fulfill a promise it has guarded for a decade.Soon, Chang’an faces an unimaginable catastrophe. A colossal cat swallows the moon, casting the city into darkness, while the Cat City crumbles and countless cats awaken to their hidden powers. In the middle of this chaos, Shen Zhaoying finally discovers the truth: the creature everyone feared as a demon was never a monster at all, but the final guardian her father had left behind to protect her.And Jinbing, the grumpy little cat that hates heights and loves dried fish, was never a coward or a deserter. For ten long years, it had remained faithful to a promise, silently guarding the man Shen Zhaoying had spent her life trying to find.