Cosima and Big Lizard have a camping sleepover with a friendly little crab. In the morning, their new friend is missing, but why?

Cosima is so excited to tell Big Lizard about her life on earth that she doesn't realise he has something exciting to say to her.

Cosima and Big Lizard investigate the cause of Dad's mysterious sleepwalking in an adventure that takes them around Proxima and right back home again.