Question self explanatory. I could google but I’ll be lazy.
Indiana Jones and the Last Crusade has a prequel preface.
Oh, good question…
What about the JJ Abrams Star Trek reboot? It kind of works as both in relation to the original series and films.
Unless you count the very short scene where Nimoy’s Spock shows how he wound up in the past, nothing in that movie takes place after the action of one of the prior films, so I would say no.
I don’t think I’ve ever seen another movie that follows a preceding film and is basically telling two separate, but thematically-related stories that are occurring decades apart like you see in The Godfather Part II. Kind of amazing if you think about it - you’d think someone would have stolen that concept by now.
X-Men: Origins?
I’m throwing out the suggestion of X-Men 2, though I’m uncertain how much of Wolverine’s story would qualify as prequel.
Technically, Star Wars I, II, and III would all qualify for semantic reasons.
Actually, Indiana Jones and the Temple of Doom happens before Raiders of the Lost Ark - the whole film.
I think the OP is looking for a movie that takes place both after and before the original, such as with Godfather Part II and the young Vito story line.
Plenty of movies have flashbacks-- How extensive does it have to be to count?
No hard rule, but I’d say more than just a scene.
The Godfather II was, very roughly, about 1/3 prequel and 2/3 sequel.
Some googling pulls up Megiddo: The Omega Code 2, which was apparently both a sequel and prequel to the Paul and Jan Crouchfinanced/produced Fundamentalist end of days movie The Omega Code, but I’ve no idea what the timeline division is there as I never saw either one.
Actually, The Last Crusade has the introduction with the young Indy that takes place before Raiders, and the rest of the movie which takes place after.
I’m trying to recall if X2 has any scenes of Magneto as a boy. But X-Men: The Last Stand has several flashbacks of what the characters did before the first X-Men movie.
That’s the one I meant when I mentioned X-Men: Origins. Damnit.
I was also going to mention one of the Bourne movies but I can’t remember which one had the flashback.
Kill Bill: Part 2 is both a prequel, a sequel and a whopping huge flashback inside a flashback.
Doesn’t that make it a prequel only? 
Terminator Salvation
It’s a sequel because it’s the next movie in a franchise.
^Then all prequels are sequels.
Right.
But all sequels are not prequels. That’s what I thought the op was getting at. Maybe I’m wrong.
Wikipedia shows a few sequels that were also prequels, including Psycho IV, Ginger Snaps Back: The Beginning, Missing in Action 2: The Beginning, Vacancy 2: The First Cut, Dumb and Dumberer: When Harry Met Lloyd, Tremors 4: The Legend Begins, Amityville II: The Possession, Cruel Intentions 2, Paranormal Activity 2, and Final Destination 5.
Although, I suppose, if your definition of sequel and prequel means it has to have all the same characters, I’m not sure if any of the above count.
Not all, but at least some overlap. For example, Vito, Tessio, and Clemenza were all dead by Godfather 2 but were in the prequel portion; Mamma Corleone (played by 2 different actresses for the pre-1920s and late-1950s scenes) was the only character who had any real screentime and lines in both prequel and sequel portion, though Michael and Fredo were shown as little boys in the prequel.