Xiao Changge, the demoted concubine-born son of the Prince Zhenbei's Mansion in the Great Zhou, was framed by his legitimate mother, Lady Su, and legitimate brother, Xiao Yunting, who slandered him for flirting with his cousin, subjecting him to family discipline, while his fiancee, Shen Qingshuang, publicly annulled their engagement. Escaping death by the skin of his teeth, his only thought is survival; a chemical engineering college dropout's soul transmigrates into Xiao Changge, armed solely with math, physics, and chemistry knowledge. He makes beauty soaps and acid-base indicators to clear his name, originally intending to save up money and run away, but is forced to open a shop due to the soap going viral. Facing suppression from family businesses, he brews strong liquor and uses saltpetering to make ice, counter-swallowing his rivals' industries. The thermite reaction startles the aristocrat Zhou Huaijin, and black powder blasting assassins startles the emperor.