the book it involved disemboweling, but remember that he asks Pazzi whether or no to cut him, with no response he says "Confused? I'll decide for you then."
Hannibal is looking at pictures of Clarice while he is playing or composing a song in the movie. In the end section of the book ('A Long Spoon') he plays this for her before and after 'dinner.'
The thief and the witness to his murder
In the book there was also a black man and woman also in charge of capturing Lecter. The man is shown in a brief shot looking at the pursuing thief. In the book, Hannibal also kills the black man after killing the thief, and the woman calls him "the devil himself" or something like this.
Clarice list using voice recognition software as a qualification for a secretarial position.
What happened to Dr. Fell's predecessor?
In the book, Hannibal's interior monologue admits that he killed him.
It is moved from the coming to America scene to the end scene.
In the novel, the drug is given to her to bypass that part of the human brain, which would not express its true feelings. In other words, saying and doing exactly what one wants.
In the movie, it is given both to Clarice (and probably to Paul) to produce suggestibility so that they will do or respond to whatever Lecter says.
In the novel, Hannibal tells Clarice to look into the Mirror to realize how beautiful she really is.
In the movie it was for her to realize that she is her own model of incorruptibility
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