On the edge of the Deep Forest lived Rockwell Cornelius Featherbottom, known simply to his friends as Rocko.Rocko and Pigg have been working on plans for their glider for weeks, and it's finally ready! When they take it out to conduct the first test, the glider soars high into the sky... and zips, swishes and loop-de-loops into a dark cave. Rocko and Pigg have no idea what could be in the dark cave, but it looks pretty scary so they go home... But they can't just leave the glider in there, can they?