Dad drops an essential gizmo in a hard-to-reach place. Big Lizard takes them on an underwater adventure to meet Ammon, the tentacled solution to their problem!

Whilst searching for new discoveries, a rockfall traps Dad, Cosima and Big Lizard in a cave. Just when all is lost, Dad finally discovers a new species!

Twig steals Cosima's volleyball. A chase leads Big Lizard and Cosima to her den... and also to a happy discovery!