The Dragonfly Race is set to begin in Piffle World, and the prize for one lucky lightweight aircraft pilot is an amazingly powerful battery in the shape of a feather. But for the four dimensions - travelers and one odd creature named Mokona, who have joined the competition, the feather represents more than energy - it's one of Princess Sakura's lost memories! And Sakura's feather isn't the only thing at stake. Despite President Tomoyo's best efforts to protect the race using her wealth and resources, unexpected hazards keep popping up, and the perilous contest could lead to death for unskilled pilots...like the princess!