It's been a year since Princess Luna's return and the Summer Sun Celebration is back again. Princess Celestia has decided to not only to commence the ceremony of the longest day of the year but to also include a tradition to allow Luna to rest for a full day. Her organizer for the event, though, has retired which leaves Princess Celestia without a task master. Twilight, her most faithful student, is a candidate for a task master and thrusts the role to her as a sign of trust.

As Twilight organizes the event, Derpy Hooves delivers a certain package for the event which makes her a very special pony.