For much of "The Notebook," the mystery hinges on whether young lovers Noah (Ryan Gosling) and Allie (Rachel McAdams) spent their lives together after being separated by her disapproving parents. Allie is drawn to another man (James Marsden) who seems to offer her more security. Poor Noah builds a whole house and grows a whole beard to impress his sweetheart. Just when we're bawling buckets over wanting these two to work it out already, we find out the answer to another mystery: the old guy (James Garner) telling the story of Noah and Allie to an Alzheimer's patient (Gena Rowlands) is actually Noah himself, trying to remind Allie that he's her husband. We're denied the happiness of knowing they did spend their lives together because now Noah is about to lie down and die next to his ailing wife. So much for happily-ever-after.
Most romantic and/or depressing line: "That's my sweetheart in there. Wherever she is, that's where my home is."