As a Royal Princess, it is Luna's responsibility to watch over the subjects in her kingdom. One of the ways she helps the common pony is to inhabit their nightmares, helping them to overcome their fears and anxieties in order to live stronger the next day. However, one night Luna steps into the dreams of a young filly and finds out that the pony is dying. With nopony else able to help the child, the Royal Princess realizes that she has no other choice but to help. Can Luna save the filly walking the line between life and death?

On a dark night filled with even darker magics, an insane cult attempts to give Nightmare Moon a body and life of her own, utterly separate from Princess Luna. But, when the spell is interrupted by Celestia, something unexpected is created.

Now, a little black alicorn filly named Nyx finds herself living under the care of Twilight Sparkle, only to be haunted by memories and emotions from her past. Is she Nightmare Moon reborn or is she simply a doppelganger with a soul and mind of her own? Can Twilight Sparkle protect Nyx from those who refuse to see past her dragon eyes and black coat?

Or, will Nyx be forced to inherit the sins that may not even be hers and become the greatest evil Equestria has ever known?