In the past, the changelings struck fear in the heart of any pony, and for good reason. But after the brave Thorax's transformation, the rest of them besides Queen Chrysalis followed suit, and they all learned to live in peace. However, Applejack doesn't buy it one bit. She's an old fashioned pony at heart, and she knows better than to buy all that hooey everypony is spouting at face value. But when even her friends tell her that there's nothing to worry about, Applejack knows she's on her own.
The only problem is that even with the entire Apple family's funding, they wouldn't have nearly enough. Scared and desperate, Applejack has no choice but to head to Canterlot and try to convince the princesses that they need to fund a great big wall for the good of Equestria.