There are two reasons that movie studios decide to make sequels: the films were envisioned as a series or they (the studio) REALLY wants some money. Easily the most referenced sequel machine in recent days is Lionsgate’s Saw franchise. Granted as these films continue to be created they’re becoming more and more for the fans (as they’ve NEVER been about how well they’re received by critics). Every Halloween when the next Saw movie comes out, I always hear people say things like “Well I’ve only seen the first two, should I go see this one?” The Saw films depend on each installment before them to continue the plot of the series, so without viewing the previous films you could be quite lost if you skip ahead.
Which brings me to the point of this post: Why would you go see a movie in a series that you haven’t seen all of the other installments for? Or for that matter, agree to review one of these films under those circumstances? Imagine seeing Pirates of the Caribbean 2, without having seen the first one or seeing the first Harry Potter movie and then jumping to the fourth Harry Potter movie.
If one of your friends wanted to see The Return of the King without seeing the other Lord of the Rings films, and you had seen all of them….why would you let your friend do that? Film series should be viewed as a whole, unless the original creators don’t consider something canon to their story (Example: The Book Wicked to The Wizard of Oz series). Even under those circumstances the creation should still be viewed in its own right as a story.
No official sequel should be left out by a viewer just because they didn’t see it/like it.