What Are Some Of Your Favourite Movie Sequels of All Time?

I have a lot of favorites, but the ones that I feel expand the original (and the overall series) the best:

- The Godfather Part II
- The Empire Strikes Back
- Aliens
- Terminator 2
- Indiana Jones and the Last Crusade
- Star Trek II: The Wrath of Khan
- The Dark Knight
- A Shot in the Dark (2nd Pink Panther movie)