Not a martian in sight

My current bedside reading material - I was sure I'd read this before, until picking it up for Freya in a bookshop.

Flicking through it I quickly realised I hadn't, and now I'm engrossed (Freya found it a bit advanced for her yet).

I suspect the combination of the film and audio versions I've come across before convinced me I had read it. Glad I've finally got round to the original!