 He has a smouldering dislike for the likes of Stone and Robinson, who are apt not to take Sedleigh as seriously as Adair would like.At first he and Mike do not see eye to eye, but they later become firm friends.A venerably white-bearded old man, a self-professed expert in eugenics, Appleby is in fact a crook, inveigling young Horace into the home of Cooley Paradene in order to rob him of his valuable collection of rare books, in "Bill the Conqueror".