17-year-old Susan and her brother 22-year-old Horace live a lonely life on Lanmoth Moor in Cumbria. Their mother died long ago, and their father Mr Scarsdale is a bitter, controlling recluse who shows them no love. Susan retains her sweet nature, but Horace bears bitterness and hatred towards everyone - though he hides it to some extent in order to manipulate others. Mr Scarsdale is bitter about a will, but the details are not disclosed until later in the story. Other characters include Roger Musgrave, whose godfather has recently died, leaving Roger penniless. He and Susan are shyly attracted to each other. When Susan and Horace's Scottish uncle, Colonel Sutherland, arrives for a short visit, he offers help to all three young people. But Horace leaves home to work for a dishonest attorney, and later experiments with blackmail, and even perhaps with murder.