Princess Luna accidentally consults a forbidden magical artifact in Canterlot Castle, and learns that Equestria is in great peril. She formulates a plan to save her beloved Kingdom, enlisting the help of the Royal Court. Together, they intervene in the life of one very troubled filly.

Diamond Tiara has had everything handed to her, but this has come at a high price; she is a bully, mistrustful of others and scornful of those she thinks of as beneath her. With the help of the Royal Court, she will be shown her life in a different perspective. Along the way, she will battle her insidious inner demons, and come to realise that, sometimes, having everything means having nothing at all.