Set sometime between the events of Keep Calm and Flutter On and Magical Mystery Cure, a crisis looms over Equestria. An entire village has been reported missing to the west. As Twilight and co. investigate, it seems more settlements will suffer the same fate as the first. Princess Celestia puts Twilight in charge of the investigation, and it's up to her and her friends to discover the cause of these disappearances, and put it to rest once and for all.