Everyone in Equestria loves the Summer Sun Celebration—except Princess Luna. She feels left out and wants something of her own. So when the Cutie Mark Crusaders propose putting on a Winter Moon Festival just for her, Luna is less than thrilled. She tries to sabotage the event at first, but as the festival progresses, her pony friends show her kindness, acceptance, and a chance to be part of something special. Ultimately, Luna learns to open her heart, accept friendship, and maybe even enjoy the celebration she once rejected.