Though Scootaloo normally appears to be a happy and lively little filly, every once in a while she reacts in a way that catches other ponies attention. Especially the ponies she spends the most time with, Rainbow Dash and her friends, seems to take notice of these little things.
When she finally reacts in a way that cannot be ignored, it is up to Rainbow Dash to find out what terrible secret Scootaloo is really hiding.