Eight-year-old Elsa's grandmother is considered wild and extravagant. But for Elsa, she's a superhero who transports her every evening to a wondrous land of knights and princesses, castles and dragons. When her grandmother dies, she leaves behind letters that Elsa must deliver to their recipients. While fulfilling her grandmother's errand, she learns much about the extraordinary life of her superhero, battles real, not fairy-tale, evil, and makes true friends.