For most of their lives, Twilight and Shining have been very competitive in their quest to get named the "sibling supreme". To win the title permanently, Shining devises a plan to hide their prized crown behind so much security that Twilight and her friends will have to go through a great deal to get it. And he's confident that this will be it, the challenge that finally causes Twilight to lose the crown to him forever.

Unfortunately, Princess Luna has a different sort of challenge for the brother-sister duo.