Twelve-year-old Nora's mom manages The Knight, a medieval theme restaurant on the verge of shutting down for good. When Nora and her new friend Mavis stop by The Knight to borrow costumes for their school play, a snowstorm hits. Nora and Mavis are trapped overnight with Diane, the restaurant's eccentric cook. Nora is familiar with Diane's many tall tales, so she doesn't pay much attention to her strange theory about hidden gold. But when they find evidence that Diane might be telling the truth, Nora starts to wonder if treasure really is hidden in the crumbling castle—and if it could save the restaurant.