What is the importance of the motion picture, Dark Passage, in the novel, The Woman in the Window?

Dark Passage is the movie that is playing when Anna sees the woman she believes is Jane Russell stabbed. Anna mentions early in the novel that this movie is: “antecedent to any movie in which a character goes under the knife to disguise himself” (35). Although no one in this particular novel has plastic surgery to conceal his identity, Anna suspects that Alistair has hired another woman to play the role of Jane to cover up the murder. Significant also about the movie Dark Passage is that the husband in the movie is trying to prove his innocence after being accused of killing his wife. When Anna calls 911 she tells the dispatcher that she believes Alistair killed Jane, an assumption that turns out not to be true.