When Bob and Mary hear of a mysterious family legend about a hidden necklace, they are determined to solve the puzzle. But their older cousin Ralph is not all that he appears to be, and the search for a secret passage takes a frightening turn.
MISCHIEF AT ST ROLLO'S Mike and Janet don't want to go away to boarding school, but when when they arrive at St Rollo's they soon settle in and have all sorts of fun and adventure with their new friends. But who is the mystery boy Hugh, and why does everyone avoid him?
THE CHILDREN OF KIDILLIN At first, when Tom and Sheila are evacuated from London to escape the war they find living with their Scottish cousins desperately unexciting. But an encounter with two strange men near a long-abandoned hut in the hills pitches the children into a thrilling adventure. Will they uncover the deadly secret in time?