On her birthday, Zaria Fierce finds her usual path to school blocked by an ugly river-troll. At first she's surprised and curious, but then Olaf threatens to eat her, which is an act Zaria could not in good conscience consent to, so Zaria counteroffers. A deal is struck and she goes to school, but Zaria is about to learn the hard way that one does not trick a river-troll and expect to win.