Su Yuniang takes over the shabbiest mud-and-thatch post station on the main road. She cooks lamb with chopped chilies, listens to travelers' gossip, and never rounds down when doing the accounts. A runaway heiress, a physician fleeing for his life, and a butcher who broke off an engagement are all put in their place by her earthy logic.
Shen Yan, a celibate junior official at the Court of Judicial Review, is secretly investigating the area in disguise as a hired hand. He means to use the Court's laws to put people in their place, but the proprietress makes him pluck chicken feathers and mend pots every day!
Then Shen Yan opens the post station's accounts and is stunned to discover that they contain secrets about the imperial family and details of a royal clan member's faked death. The old warhorse eating grass in the back yard bears an imperial brand, and the ruined cellar is connected to the replacement of the true royal heir!
When political assassins from the capital besiege the post station, powerful figures from every corner of the martial and common worlds draw their blades to protect them. Shen Yan draws his sword and shields her. "The Court of Judicial Review's laws state: anyone who harms my wife will be executed on the spot!"