Some years have passed since the horrors of the Rainbow Factory, and it is almost a forgotten nightmare, until Windy Skies' sister Night Sky fails her flight exam and is badly injured. Running to her aid, Skies is automatically failed for refusing to leave her injured sister alone. Nopony knows where you go when you fail, but four ponies now deemed to be "failures" are about to find out. With Doctor Atmosphere and Rainbow Dash free, anything is possible.