Simpsons Season 17, Episode 13: The Seemingly Never-Ending Story

While cave exploring with his family, Homer causes the cave to crumble and finds himself stuck upside down in the ceiling. Marge and Bart search for help while Lisa passes the time by telling Homer a story, which turns into a chain of narrated tales that, bit by bit, explain why The Simpsons are spending the day at Carl's Dad Caverns.