Rocking Horse War

One sunny morning the triplets disappear, leaving only a few mysterious clues behind: an open upstairs window, three missing rocking horses and some strangely shaped marks on the lawn outside. Could they be hoofprints? Used to their silly pranks, older sister Pearl sets out to find them. At the garden gate she encounters Thomas, the snooty grandson of a local earl, who warns her that the moors aren't safe today...