When Scootaloo finds a hidden cave in the Everfree Forest, she decides to explore. Under normal circumstances she would've taken Sweetie Belle and Applebloom, but Sweetie was getting ready for a play and Applebloom had to help her family with the harvest.
But when Applebloom and Sweetie Belle notice that Scootaloo has disappeared, they investigate- and embark on an adventure that could end in two ways, destroy Ponyville, or save it.

-will be fixed-