What should have been an ordinary Danish Christmas for twelve-year-old Bettina Larsen and her baby sister, Pia, quickly turns extraordinary when unexpected events take their parents away for a few days, leaving Bettina in charge of the house, the barn, and baby Pia. In all the confusion, Bettina’s family neglects to set out the traditional bowl of Christmas rice pudding for the tiny nisse, a gnome-like creature who’s rumored to look after the family and their livestock. But no one besides her grandfather Farfar ever believed the nisse were real, so what harm could there be in forgetting this silly custom? But for one young and impetuous nisse, the lack of rice pudding is a very big deal. And when baby Pia disappears during an afternoon nap, Bettina finds herself trying to appease a nisse she’s not even sure she believes exists. With her parents’ return looming, Bettina must do everything she can to get her sister back and set things right—even if it means entering the magical world of the nisse.