Emily Brontë's 1847 novel Wuthering Heights portrays distinct mannerisms of each character, but William Wyler's 1939 film does not capture these characteristics well. The difference in Heathcliff's character is striking. In the novel Heathcliff is depicted as a devilish looking man with callous, vengeful feelings.
Heathcliff's appearance in the movie, as depicted by Rex Downing as a child and Laurence Olivier as an adult, is not what I pictured it would be when I was reading the novel. Brontë described Heathcliff as looking exceptionally different from Cathy or Hindley, almost evil. The characters in the movie talk as if Heathcliff looks unique, but I do not see much difference between him and Edgar, played by David Niven, or Hindley, played by Douglas Scott as a child and Hugh Williams as an adult.
Heathcliff's attitude in the movie is not nearly as malicious as in the novel. We, as viewers, believe Isabella is treated worse in the novel than in the film. In the novel, Heathcliff treats Isabella so badly that she leaves him not long after they were married. In the movie, Heathcliff is never seen beating Isabella, acted by Geraldine Fitzgerald, or talking shameful to her; but he is only seen ignoring her while she pleads for his attention. Heathcliff must not have been too bad to Isabella because she wishes Catherine, depicted by Merle Oberon, to die so she may acquire his love.
Heathcliff's temper in the novel is much worse than in the film. That is learned by his squabble with Edgar Linton at the beginning of the novel. Heathcliff has worked hard at looking nice for company, and Edgar insults him by comparing his hair to a horse. In spite, Heathcliff throws hot applesauce into Edgar's face. In the film, no such interaction takes place. Heathcliff only refuses to take care of Edgar's horses, and there are no violent confrontations.
Unfortunately, the last section of the book is not in the movie. That section shows how low Heathcliff really can go. Not only does Heathcliff use the daughter of his beloved Catherine to obtain revenge on the Lintons and the Earnshaws, but also he uses his own son. In both the book and the film, the characters talk of how evil he is, but we do not see it as clearly until this point. Even though the film portrays Heathcliff as a hero, the book portrays him as a villain that, in the end, gets everything he deserves.