Psycho (1960 film)
Screenplay

Smith likewise mentions the absence of a hotel tryst between Marion and Sam in the novel. For Stefano, the conversation between Marion and Norman in the hotel parlor in which she displays maternal sympathy towards him makes it possible for the audience to switch their sympathies towards Norman after Marion's murder. When Lila is looking through Norman's bedroom in the film, she opens a book with a blank cover whose contents are unseen; in the novel, these are "pathologically pornographic" illustrations. Stefano wanted to give the audience "indications that something was quite wrong, but it could not be spelled out or overdone". In his book of conversations with Hitchcock, François Truffaut says the novel "cheats" by having extended conversations between Norman and "Mother" and stating what Mother is "doing" at various given moments.
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