Cosima takes over Dad's mission to film a unique underwater plant. But his special camera proves harder to operate than she'd thought, and Big Lizard keeps getting distracted.

Rex is missing, but Dad, Cosima and Big Lizard need him to save them from a giant slug!

When Dad's Lizard Translator malfunctions, Cosima is carried away by a giant beetle! Cosima and Big Lizard realise they don't need to speak the same language to be best friends.