Margot, Wesley and Josephine have got an awesome weekend mapped out for the end of the holidays before they start high school - and they don't want anything to stand in the way of their BIG plans in London. But when they are staying with Margot's mum and her new boyfriend Teddy in Notting Hill, something happens that they just can't ignore...

Join the kids as they follow the case across wild West London, following the trail of a super creative murderer as well as some epic street art. From skate parks, tower blocks and canal towpaths they end up on a float at the colourful Notting Hill carnival - the biggest party of the year! How will they piece together the evidence to solve the mystery at the heart of London's coolest sights?

Praise for Sharna Jackson: 'I utterly loved The Good Turn; it's bone-deep brilliant; a joy to the very end. It's so warm and so funny, and so ferociously on the side of justice and of hope. I adored it.' - Katherine Rundell