Applejack receives a letter from her parents. there's just one problem, they've been dead for many years. From all the main six can figure out, the letters details of a secret facility far beyond the Crystal Mountains where Applejack's parents presumably worked. Even though the letters left behind by them tells them not to go, they have to check out what happened up north, what happened to Applejack's parents, and why did they disappear from the Apple Family so many years ago.

This story is a Penumbra/MLP crossover.