While being treated for asthma at a country spa an American diplomat's lonely 12-year-old son is befriended and infatuated by a suave mysterious baron. But soon his adored friend heartlessly brushes him aside and turns his seductive attentions to his mother. The boy's jealousy and feelings of betrayal become uncontrollable. The story is set in Austria in the 1920s.

The book was adapted for a movie in 1988 starring Faye Dunaway Klaus Maria Brandauer and Ian Richardson.