Sister by Rosamund Lupton

A very exciting, fast paced, easy to read novel. It is about a young woman who goes missing and her sister's quest to discover what happened to her. The characters and plot are both entirely unrealistic (some of the characters staggeringly so) but it's a good story nonetheless. It is less gruesome and more intelligent than a lot of murder mysteries. If you like thrillers, this is a good holiday read.