The foggy feeling like you're wandering through a dream, disconnected from the world around you. Sunset Shimmer experiences that every day. Ponies struggle to remember her, she suffers from random bouts of exhaustion, and at eighteen, she still has no cutie mark.

Despite the claims her mother makes, Sunset knows she is broken in some way. It isn't until her nineteenth birthday that she discovers why.

When her perception of herself and the world around her shatters, Equestria will face the consequences of the villain... or the hero, it was never supposed to have.