Since banishing her sister to the moon, Princess Celestia has fallen into a state of depression that she seems incapable of escaping from. Plagued by guilt and reoccurring nightmares over the role she believes she plays in her sister's downfall.

To try and alleviate these concerns, Princess Celestia decides that she needs to take on a student, somepony to wield the Elements of Harmony and ensure her sister's freedom from the forces of evil. There's just one problem, not many ponies are able to mentored directly by a princess.

But one night, Celestia has a chance encounter with a little filly that will change her life forever. A filly with a destiny that nopony can see, and the potential for something greater than what she currently is. Even if what that is is unknown.