|Series||The Grim Adventures of Billy & Mandy|
|Cartoon Network US Premiere||January 27, 2006|
|Paired with||Giant Billy And Mandy All-Out Attack|
Giant Billy And Mandy All-Out Attack
Billy finds a caveman (Fred Flintstone from The Flintstones) while trying to dig up the center of the earth so he can live there because the surface is cold but the caveman goes berserk and kidnaps the teacher so it's up to Billy and the gang to save their teacher.
- Story by: Maxwell Atoms and Alex Almaguer
- Storyboard by: Alex Almaguer
- Directed by: Shaun Cashman
- Mandy: Well, he's trying anyway.
- Both: (Chewing the Ribs)
- Harold: (Burps)
- Billy: (Growls)
- Barney Rubble, and Betty Rubble appeared in the credits except Wilma.
- Fred Flintstone, doesn't speak (except says his own name while introducing himself to Billy) in this episode but only grumbles and says his famous line, "Yabba Dabba Doo!" (Sometimes “Yabba Dabba!”)