In an Equestria not quite what it seems, Princess Cadance is tasked by her Aunt with overseeing the Summer Sun Celebration, accompanied by Captain Shining Armour. But why is the guard being increased? Who are the two odd mares in Ponyville? And why do so many recent events correlate to a popular novel?

Force Captain Adora and Horde Solider Catra are sent to infiltrate The Rebellion, right as Princess Glimmer of Brightmoon is being sent to help Princess Entrapta of Dryl with a little friendship problem regarding an out of control experiment on a group of pre-First ones artefacts known as the Elements of Harmony...