Dr. Martin Dysart (Richard Burton), a psychiatrist who has grown unhappy with his life, takes on the peculiar case of Alan Strang (Peter Firth), a reserved teenager who has been accused of brutally blinding six horses. Dysart slowly unravels Alan's background, learning that he grew up in a strained household with a devoutly religious mother (Joan Plowright) and an atheist father (Colin Blakely). But as Dysart begins to trace the roots of Alan's problems, his own also begin to surface.