Lin Lengqing, a modern doctoral expert in toxicology, transmigrates into the body of an abused legitimate daughter. From the very beginning, her stepmother poisons her, while a treacherous prince frames her. Facing what seems like certain death, she uses her scientific knowledge to turn the tables. She exposes deadly arsenic poisoning with an ash test and saves her dying grandmother by detoxifying her with silver needles. When her enemies present an exotic Western Regions flower to harm her before the Emperor, she prepares a color-changing reagent on the spot, exposing the Seven-Star Begonia as it carbonizes before everyone's eyes. Joining forces with the Ninth Prince, Ye Jingyuan, she presents irrefutable evidence of embezzlement and privately manufactured weapons, bringing the Prince of Chu and the entire Zhao clan down. From seizing power within the household to bringing criminals to justice at court, she carves out a path of overwhelming revenge with modern intelligence and ruthless determination. Ultimately, she joins forces with the cunning Imperial Uncle, and together they stand above the world.