The Shen family, the hereditary Marquis of Northern Defense, was falsely accused and framed by treacherous officials, bringing disaster upon the entire clan. Only Shen Lie narrowly escaped with her life. Disguised as a man, she concealed her identity for ten years, relying on extraordinary martial arts and exceptional intelligence to infiltrate enemy territory and wait for an opportunity to enter the palace. Zhao Heng, an absurd emperor who, in the eyes of the world, spends his days fighting crickets and wandering the streets, has actually been concealing his true nature since ascending the throne at the age of seven, all to uncover the mysterious truth behind his elder brother's death. One seeks to clear her family's name, while the other seeks to uncover an old case hidden within the imperial court. Carrying their own secrets, the two meet within the palace walls. From mutual suspicion and testing one another to joining forces and devising a plan together, they work to expose the treacherous officials, restore justice to the realm, and finally overturn a long-standing injustice.