Darren Shan’s Demonata series needs nerves of steel even before you’ve opened the snarling, glow-in-the-dark covers. Grubbs Grady’s parents invoked a magical family bargain in the hope of saving their daughter from turning into a werewolf. Poor Grubbs found them eviscerated in the first book, and went mad. Sent to live with his uncle and half-brother, he, too, discovered he could only save the ones he loves by playing chess against a demon in Lord Loss.Having won in the first book, he ought to be happier in Slawter, but, as he warns us, there are no fairytale endings. Uncle Dervish still suffers from appalling nightmares, so it’s a bit silly of him to hook up with a cult horror-movie director to advise her on how to make a film about demons. Grubbs and his half-brother Bill-E come along as extras to the village of Slawter, and soon find that the special effects are just a bit too bad not to be true.As grossly entertaining as ever, Grubbs’s cynical teenaged voice carries the story along like a bat out of hell. There is an obnoxious child-star, Bo, who turns into one of those feisty heroines, and a rather predictable climax, but the most memorable character is the obsessive director, Davida, bent on creating an immortal horror film. Inevitably, she discovers that, when supping with the Devil, YOU are your just desserts.Both Delaney and Shan share an interest in salvation and redemption, and you can hear the oral tradition of Celtic storytellers in their hypnotic prose – just as you can in Eoin Colfer and Herbie Brennan, whose latest thrillers will also be springing demons on us later this year. Strong imagination may, as Shakespeare said, make us suppose a bush a bear but we all love a chill down the spine during these hot, midsummer nights.