Mr Wishmore's class, including the Toothless Wonder and his friends, enter enthusiastically into their teacher's scheme to save Rocksea pier from developers. But there is one boy who is not happy - Start Sedgemoor whose father wants to build a marina in place of the pier. When Mr Wishmore receives a threatening letter about his support for the pier campaign, it is up to the Toothless Wonder to devise an ingenious scheme to thwart the developers...