Sunset Shimmer has betrayed Celestia and entered the mirror to another world. However, the first day in this new world would change everything when an accident causes Sunset Shimmer to lose her memories.
A handicapped unicorn, a carnivorous earth pony, a digging pegasus with acrophobia, and a pony-changeling hybrid walk into Ponyville. Things can't go wrong, right? Right?
In Canterlot, life should be perfect. But every now and then somepony decides they don’t want their lives. That’s when I come into the picture. After I’m done with you, you won’t remember anything at all. I am Amnesia.
When Trixie is hospitalized with amnesia, there are only six ponies up to the task of bringing Trixie back. To bad the mare is absolutely terrified of them.
Rainbow Dash wakes up in a bed of flowers in a cave as a filly with amnesia. Lost and confused, she's taken in by a goat monster named Toriel. That's okay though, as long as she has DETERMINATION she can get through this.
A unicorn awakens in a forest to discover he has no recollections of his past or how he got there. He finds his way to Ponyville where he tries to regain his memory, and begin a new life.