Daisy Wells and Hazel Wong are the secret detectives at the Deepdean School For Girls. Their mysteries aren't exactly exciting, though, until Hazel stumbles across the body in the gym. The body vanishes, but Hazel and Daisy are on the case, digging up secrets and clues. Daisy plays Sherlock to Hazel's Watson, with Daisy's ruthless pursuit of answers restrained by Hazel's sense of the human horribleness at the heart of it all. Gently but fondly and sensibly playing with the conventions of boarding-school stories and Agatha Christie stories and making a study of a particular Holmes/Watson pairing, Stevens keeps the story focused like a laser on the mystery, playing fair, but providing surprises and satisfaction with the solutions. The characters are endearingly flawed but lively and fascinating, the setting is wonderfully evoked, providing the reader with a strong, witty start to a hopefully enduring series.