After hitting a wall in the job market as a fresh graduate, Shi Yi reluctantly returns to his village and opens a small supermarket—only to accidentally unlock a cross-time portal and welcome his first customer: He Linlang, a female general of the Great Liang dynasty, clad in armor. From initial shock and confusion to trading modern goods for ancient gold and silver, Shi Yi rapidly builds wealth through this magical supermarket and even binds himself to a cross-time trading system. Meanwhile, He Linlang uses the supermarket's grain and medicine to break her army's siege. Through each transaction, the two weave together adventures across two eras, launching a two-way cross-time partnership.