It was a nice warm afternoon at Sweet Apple Acres, and Applejack was, well, bucking apples. She the notices one of her trees were turned to crystal. First thinking it was a sick joke, she asks the unicorns around town if they know anything about it. When everyone says no, she then consults Twilight, who still isn't sure why. But soon she will find that the crystallization of the tree is just one hint out of the few that will lead the mane six on a mission to find out who is doing this, and why.