Su Zijin, the final head chef of the Great Yan Imperial Kitchen, is betrayed by his senior fellow apprentice and forced to jump off a cliff. He time-travels to modern times and is taken in by Lin Xiaoman, a young woman running a midnight diner delivery stall. Using a lost recipe, the Jade Dew Frost Cake, he makes the stall go viral, and the two naturally start a Great Yan Imperial Banquet delivery business. Su Zijin discovers that the delivery box can connect to the ancient battlefield, thereby forming a closed-loop of saving the country by earning money to buy supplies in modern times and cashing in ancient artifacts in return. While resisting the conspiracies of his senior apprentice and speculators, they investigate the mystery of the Dragon Cauldron, and ultimately defeat their six-hundred-year-old grandmaster with the three true fires of trust, righteousness, and affection, opening a never-closing "Ancient and Modern Diner" between the two realms.