Several months have passed since Luster Dawn embraced friendship and moved to Ponyville. Despite a few bumps along the way, she has settled in well and even has her own group of friends.

One day while going through one of the Castle's libraries, Luster discovers a strange mirror, one that leads to an entirely new world. Unable to help herself. she sets out to explore what could be on the other side.

Twilight and Starlight can only sit back, and enjoy the show.