The Octonauts venture inside a whale shark again (from Season 1), this time to rescue a porcupine pufferfish.
Tropes:
- Disney Death: Mild example. After rescuing Puffy, Peso can't find Barnacles and believes he's been dissolved by the acids in the whale shark's stomach. However, soon after, Barnacles emerges safe and sound.
- Oh, Crap!: When Kwazii realizes he forgot the Fish-Pack.
- Sequel Episode: To the first episode, "The Whale Shark".
