The Secret Seven are always ready to solve a mystery in this much-loved series of 15 books by Enid Blyton, brilliantly illustrated by Tony Ross. .Solve the mystery with the Secret Seven – everyone’s favourite detective club! These timeless stories are perfect for young fans of mystery, adventure or detective series.In book eleven, Jack’s little sister, Susie, is so annoying! The Secret Seven are furious when they discover she’s formed her own “detective gang”! Then some money is stolen, and Susie is a chief suspect.Solve the mystery!