Leon Garfield's latest, The Strange Affair of Adelaide Harris, is a glorious, non-sensible frolic, with carefully erudite period roots, that will charm and refresh adults as well as the teenagers for whom it is primarily intended. Garfield has always seemed to have power to summon the ghosts of both [Robert Louis Stevenson] and Dickens to his elbow when he starts to write, interweaving the sinister blood-chill of Blind Pew and Long John Silver with the stench and slime of Simon Tappertit and cronies' underground cellar. But this time he's taken an unexpected turn into the sunlight, and added Saki to his established familiars. A lovely outburst of joyful, impudent satire has resulted, with horror and violence in full retreat. What's more, Mr Garfield has dared to come all out on the side of age against youth, and it is the plans of the over-cocky young that go astray...