I have not read Nicholas Sparks' The Notebook, but I have heard good word-of-mouth about the novel. Sadly, the elements that made the book special did not survive the transition to the screen. The Notebook, as adapted by Nick Cassavetes from a screenplay by Jan Sardi and Jeremy Leven, comes across as an ordinary romantic melodrama with a maudlin and ineffective climax. It's the kind of story for which no term seems more appropriate than "soap opera."
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