The gang visits Cinco, Mexico for a fiesta, but find it's been cancelled because of the ghost of King Katazuma, a vengeful Aztec king. Consequently, the teens set out to investigate the mystery.
This episode includes examples of the following:
- Giant Footprint Reveal: Early on, the Mystery Machine falls into what Velma thinks is a giant chuckhole. Shaggy points out that the chuckhole is actually a giant footprint, but Fred tells him that nobody is tall enough to make a footprint that size. It turns out to have been left by a giant Aztec statue.
- Living Statue: King Katazuma brings a giant Aztec statue to life as an ally.
- "Scooby-Doo" Hoax: The culprits are using their King Katazuma and Aztec statue disguises to scare people away from a pyramid, which they're robbing.
- Unholy Matrimony: The culprits turn out to be a husband-and-wife pair, using their monster disguises to keep people away from a pyramid they're looting.
