Originally Posted by Beantown Bronco
Not even close.
Just off the top of my head, these had really good first and/or second chapters and FAR worse third installments:
Beverly Hills Cop
Spider Man (Tobey Maguire versions)
these are debatable though. Unlike The Dark Knight trilogy most of these series were either mediocre, or the 2nd movie in the series was terrible as well. Austin Powers had a good opener a mediocre middle and a ****ty finale. Jurassic Park was garbage after the 1st movie as were The Matrix and The Mummy. I never cared for Raimi's take on Spider-Man, so i will withhold judgement.
The Godfather is the best comparison to The Dark Knight trilogy. in that the first 2 were great and the third was garbage. I have always had a theory about Godfather 3 though. If it were a standalone movie, that had no connection to 2 all time great movies, would it still be seen as terrible? I just have always felt it was an ok movie, it was just a massive letdown after 2 classics.