Twilight Sparkle and her friends are invited to the Crystal Empire to attend the Crystalling, a magical ceremony honoring the birth of Princess Cadance and Shining Armor's foal. Twilight brings her new pupil Starlight Glimmer to the empire to reconnect with Sunburst, her estranged childhood friend, as part of her first friendship lesson. Starlight, however, is anxious to keep Sunburst from learning of her past villainy and tries to avoid the reunion. The two eventually meet, and following an awkward conversation with him, Starlight assumes Sunburst to be a successful wizard who has moved on from their friendship. Meanwhile, Twilight is shocked to discover the foal is an alicorn filly with powerful, uncontrollable magic. The filly's cries shatter the Crystal Heart that protects the Empire, leaving the city exposed to a deadly snowstorm.