Eight-year-old Princess Anna lives in the castle of Erendelle with her parents and a sister who no longer speaks to her. When the king and queen leave on business for a few days, loneliness and boredom completely take over Anna. Luckily, she manages to meet a royal messenger, who comes up with a great idea for her to have fun—writing a letter! And even if the friend for correspondence had to be invented, it doesn’t matter: sending mail turns out to be very interesting anyway. So how surprised Anna is when replies begin arriving to her letters! Who is writing back to her?