I recently read The Enemy after picking it up in Waterstones (met Charlie at the same time and got it signed...thoroughly nice bloke).
It's a really easy, but gripping read.
Under 14s are the only survivors of a deadly plague, which turns Adults into zombie type creatures. It's a good survival tale of how kids would deal with a situation like that.
Really recommend you check that one out.
Really enjoyed that book aswell, though didn't realise when i first started reading that it was the first book for the story and that it's going to have at least one follow up, so the ending kind of caught me off guard. A real easy read, much like Dan Brown, it's not the greatest piece of literature you'll ever read but it's an easy read and always enjoyable.