Thought to have been killed as a filly, Twilight Sparkle is discovered to be returning to Canterlot. Instead of a joyous reunion awaiting her, a trail of destruction follows her as Celestia and Luna struggle to discover how, and why, she's returned.
To keep her job at the library, Twilight Sparkle must face her greatest challege, one which will push her very sanity to the breaking point. No, not the Cosmic Horror stirring in the dreamvoid between universes, worse: Library Patrons.
A trip to see the dragons sets in motion a chain of events that leaves Twilight and Celestia in a desperate struggle against ancient evils long thought defeated. Something dark is stirring in the east...