Airdate: 1990
When Bentley accidentally destroys Bert's new RC car, he turns to one of Colonel Jethro Smith's treasure maps to repay the debt, resulting in him and the Pigs getting trapped in the Endless Echo Caverns.
Easy Money! contains examples of:
- An Aesop: Making the money you need requires hard work and patience, and there are no foolproof shortcuts to getting it.
- Anger Born of Worry: When Lisa finds Bentley, she chews him out for going to the Endless Echo Caverns alone without telling anyone where he was going, but she quickly gets over it and focuses on rescuing him first.
- Answer Cut: When Cedric points out that the map of the Endless Echo Caverns indicates a stream used to flow through it, Bert wonders where all the water has gone. Cut to Bentley and the Pigs, whose area of the caverns they're trapped in is slowly filling with water.
- Big Sister Instinct: After learning that Bentley might be lost in the Endless Echo Caverns, Lisa comes up with a plan with Bert and Cedric to rescue him.
- Chekhov's Gun: When Lisa is first seen working at the Evergreen Museum, Professor Smedley-Smythe mentions that his maps of the Evergreen Forest are the most detailed. Bert, Lisa, and Cedric later have to borrow his map of the Endless Echo Caverns for their rescue mission.
- "Could Have Avoided This!" Plot: Lisa realizes that Bentley wouldn't have gone on the treasure hunt if she just gave him the money he needed.
- Drowning Pit: Bentley and the Pigs get trapped in an area of the Endless Echo Caverns slowly filling with water, which require Bert, Lisa, and Cedric to wear scuba gear to rescue them.
- Fool's Map: Colonel Jethro Smith's treasure maps turn out to be a scam, as Cedric tells Bert and Lisa that his father found that out the hard way when he spent three days in the Endless Echo Caverns going in circles following one.
- Foreshadowing: Professor Smedley-Smythe mentions his brother as he admires Lisa's working attitude and says that he "never did find him". Later in the episode, Lisa's brother Bentley is presumed missing after he gets lost in the Endless Echo Caverns searching for treasure.
- It's All My Fault: Lisa blames herself for Bentley going missing, realizing she was too stubborn to give Bentley the money he needed to pay off Bert's RC car.
- Mail-Order Novelty: Bentley sees the ad for Colonel Jethro Smith's treasure maps in the back of a comic book.
- No Time to Explain: Bert, Lisa, and Cedric borrow a map of the Endless Echo Caverns from the Evergreen Museum to help with their rescue mission, but when they bump into Professor Smedley-Smythe and he asks where they're going with the map, Lisa tells him that she unfortunately doesn't have any time to explain.
