Long ago two alicorn Sisters ruled Equestria. One controlled the sun, the other the stars. It has been 1000 years since the younger sister was banished to moon after becoming Deepened Dusk. Now Starswirl, gifted unicorn and prized pupil of Princess Sunset Shimmer, believes that Deepened Dusk will return to seek revenge on Equestria. The only thing that can stop her are the Elements of Harmony, but they have been lost to time. Will she be able to find them in time with her new friends?