Love Actually (2003)

Continuity mistake: After Sarah has called at Harry's office, Harry prepares to open his office door to see her out. The camera cuts back to Sarah for a moment, then back to the camera angle on Harry as she walks to the door. In that short space of time, the sliding cupboard doors have changed their configuration, and the blinds in the upper left of the frame have partially closed. (00:18:45)

elleblue

Karen: Tell me, what would you do in my position?
Harry: What position is that?
Karen: Imagine your husband bought a gold necklace and come Christmas gave it to somebody else...
Harry: Oh, Karen...
Karen: Would you wait around to find out if it's just a necklace, or if it's sex and a necklace, or if worst of all it's a necklace and love? Would you stay, knowing life would always be a little bit worse? Or would you cut and run?
Harry: Oh, God. I am so in the wrong. The classic fool.
Karen: Yes, but you've also made a fool out of me, and you've made the life I lead foolish too.

Trivia: Any viewers outside of Britain might not get the joke when Billy Mack isn't sure which one is Ant or Dec. They are very well known in the UK, and dominate Saturday night telly. The joke refers to the fact that even though they are popular, a lot of people don't know which one's which.

Question: Even if Karl and Sarah don't get together at the end, I couldn't see what exactly was stopping them?