Future universe. "Sister" Princesses Sunset Shimmer and Twilight Sparkle mourned the loss of Equestria's favorite Princesses - The royal natural-born alicorn sisters Celestia and Luna. In an attempt to win them back, they resurrect them - as fillies.
Last night, Celestia was surviving in the wilds of the land. The next morning she wakes up in a castle with everypony calling her Princess. Everything in her life is now upside down. Worse, her baby sister Luna is missing!