Okay, here are three VERY popular trilogies
Star Wars
Indiana Jones
Back to the Future
What are your favorite single movies from each of the trilogies?
I vote for:
Return of the Jedi
The Last Crusade
and, Back to the Future III
Hmmm…you voted for the third installment in each trilogy.
Personally, I’d go the other way, for whatever reasons I liked Raiders of the Lost Arc, Back to the Future I, and whatever the first starwars was called (New Hope?? I think), the best.
I’m going 2, 3, 1.
Empire Strike Back
Last Crusade
Back to the Future
For a second I thought you titled this thread “trilobites”.
Empire
Raider
II
(Or, “Things on the average Roman’s mind in the year 100 AD.”)
Jedi
Last Crusade
Back to the Future
Empire Strikes Back
Raiders of the Lost Ark
Back to the Future II
Umm. This is hard.
OK i’m skipping the first two 'cause I haven’t seen all/any, and don’t really like them.
Back to the Future II.
[hijack]
The Xanth trilogy, by Piers Anthony.
That’s up to, what, 13 books?
[/hijack]
Empire
Crusade
Back to The Future
Dragons of Winter Night
He always said he was really bad at math. 
I like Mostly Harmless, the fifth book in the increasingly-misnamed Hitchhiker’s Guide trilogy.
But my favorite trilogy has got to be the Disgusting Characters trilogy. (Mostly 'cause I’m in the midst of writing the 3rd installment right now. )
Jedi is probably tops–more good action/fighting/flying scenes.
Last Crusade is a fantastic movie, but I think I could watch Raiders more often.
BttF I, by far.
Empire Strikes Back
Last Crusade
Back to the Future II
Goose, I completly forgot about the Chronicals trilogy! Damn me!
Okay, in that trilogy (which is four books)
I vote for Dragons of Autumn Twilight.
Empire
Last Crusade
BTTF I
Jman
The first of all three was the best. None of the sequels was up to the level of the original, though Empire and Last Crusade were good movies.
The general rule of most trilogies is that they go down in quality as the series goes on. The only movies that bucked this trend were the Mad Max films – Mad Max II (The Road Warrior) is much better than the original, and Mad Max Beyond Thunderdome is just as good. Also each of the first three James Bond films was arguably better than its predecessor (though they never reached that level again).
In book series, only Terry Pratchett has managed to keep on a high level, and even improve as the series went on (with only one or two so-so efforts).
Am I the one who will have to mention:
Evil Dead
Evil Dead II
Army of Darkness
