When Barnacles and Peso crash the Gup-H in the Yucatan Jungle, to get Coba the little octopus home, they have to dive in the Sac Actun Caves to reach the Caribbean Sea. Unfortunately, the caves challenge Barnacles' claustrophobia and the crew has no easy way of finding them. While the other Octonauts search for them on the Caribbean side of Mexico, Barnacles and Peso must navigate their own way through with the help of Ryla, a cave-diving expert. But can the crew find them before they suffocate?
The episode has the following tropes:
- A Day in the Limelight: This special focuses on Peso and Captain Barnacles bringing Coba the little octopus home by navigating in the Sac Actun Caves.
- Foreshadowing: In the trailer, Captain Barnacles had a worried look when he, Peso and Coba entered the caves. It turns out he's claustrophobic and going inside the caves reminded him of how he was trapped in a tight space with said inside a cave.
- Running Gag: The iguanas saying "Not everybody who goes into the cenote, comes out of the cenote."
- Kwazii even LampShades this.Kwazii: Is that all they know how to say?!
- Kwazii even LampShades this.
- Wham Episode: Ooh boy, where do we begin?
- The debut of the Gups Q and G.
- Captain Barnacles has claustrophobia ever since he was a cub and the Sac Actun Caves are a reminder of how he trapped in some white caves.
- Before becoming an Octonaut Dashi worked with a partner named Ryla and both went cave diving before. And she even wrote a book on it.
