After a year at the king's palace, Miri has learned all about being a proper princess. But the tables turn when the student must become the teacher! Instead of returning to her beloved Mount Eskel, Miri is ordered to journey to a distant swamp and start a princess academy for three sisters, cousins of the royal family. Unfortunately, Astrid, Felissa, and Sus are more interested in hunting and fishing than becoming princesses.
As Miri spends more time with the sisters, she realizes the king and queen's interest in them hides a long-buried secret. She must rely on her own strength and intelligence to unravel the mystery, protect the girls, complete her assignment, and finally make her way home.