Before Anna saved Elsa in an act of true love, she was a young girl looking for a friend … Her sister, Elsa, seems determined to avoid her, and all Anna wants is a friend to play with. She imagines another girl her own age, Astrid, and sends her a letter. To her surprise, Astrid writes back! But as the two become friends through their letters, Anna begins to wonder if Astrid is closer than she first thought …