Whilst Dad is stuck in the desert, D.O.R.I.S. tries to give Cosima and Big Lizard a lesson on friction. As things begin to heat up, a creature steals Cosima's only means to locate Dad!

Dad's favourite record won't play anymore, so Cosima and Big Lizard secretly plan to learn the song and surprise him. However, they have trouble recruiting a drummer.

Big Lizard and Cosima create a fantastic water ride when they dislodge an underwater rock blocking a volcanic vent. It's all good fun until they realise the sea is starting to change.