For almost a year now, Trixie has been sending letters to Twilight. The only problem is, Twilight hasn't gotten a single one... until today. But now that she has, Twilight is left with more questions than she knows how to answer. Fortunately, she has a plan. Unfortunately, she doesn't know if that plan will work.
Twilight receives a letter from Trixie one day, but it raises more questions than it answers.
Trixie's travels bring her to the mountain city of Frostvale, and Twilight struggles ever northward in an attempt to catch up with Trixie.