As punishment for her crimes, the Elements have cursed Sunset Shimmer to do favors for anyone who asks. Lucky her. And then there's that other Twilight Sparkle she keeps running into...
The girls have returned from Camp Everfree with new powers and pressing questions about them. They won't have much time to find the answers they want as the sky above them shatters, dropping pain, anger, and hope through the void between worlds.