This is one of my favourite books.

It is about Emma, a girl who grew up in Botswana, who spends the summer with a group of very eccentric relatives in Scotland. Emma is thrown into a grown-up free zone, as her cousins do whatever they like and on a grand scale. For example, fixing an ancient Victorian submarine and going on risky underwater journeys in the loch.

The adventurous aspect of the book is important, but so is the process of Emma sussing out her cousins, and being judged in turn. The characters are unusual but completely believable and the situations are gripping.

I have a weakness for underwater adventures, and this one is just fascinating. It's fun to learn about the details of how the ancient two person submarine works. And the most interestng aspect of the story is Emma's moral dilemma; how to deal with the secret revealed by the submarine voyages.