The sage Mandialix and his apprentice, Hormiga, are inadvertently involved in a dangerous adventure. A nobleman has recruited the three best hunters of the river (and Mandialix against his will), to satisfy the new whim of the king: to capture the last grifonicorn to include it in his collection of mythological creatures. But one night, Ant discovers that the search for the beast is nothing more than an excuse, part of a secret plan much darker than he could ever have imagined.