Princess Twilight Sparkle's crown, the element of magic, is stolen by Sunset Shimmer who disappears into a mirror that leads into the human world. Twilight and Spike go through the mirror to chase after her and transform into a teenaged human girl and a talking dog, respectively. They meet friends that resemble their pony friends from Equestria, with whom Twilight works to become Princess of the Canterlot High School Fall Formal and win her crown back from Sunset Shimmer.
