This wonderful, twisted gothic novel won the Times/Chicken House children’s fiction prize in 2018; happily, I was one of the judges. It stood out then for its evocation of a weird and wonderful world with compulsive characters and a cracking mystery at its core. Since I read that early manuscript Trudi Tweedie, a former beer researcher who lives in Aberdeenshire, has polished her dark, deep story until it shines as brightly as Iseabail’s pearl.