There is a thing about Star Trek films; the odd numbered ones tend to suck. The even numbered ones, like The Wrath of Khan and this one (being the tenth Star Trek movie), also tend to suck.
This film also happens to be the end of the run for the Next Generation crew (named that because their series is set approximately three generations after the original Star Trek). Patrick Stewart (Captain Jean Luc Picard) asked to be let out of his three film contract three films ago, but was forced to gut out the role he loathes one more time. It shows.
Data: Captain, there is a ship coming into sensor range.
Picard: Yes. Of course. Man, we sure are in space. Hey, let's all go on board the holodeck so that it can almost kill us again.
(Picard takes a drag off a poorly concealed cigarette)
Data: The ship, sir...
Picard: Ram it!
Worf: Perhaps we should bring it up on the view screen.
Picard: Ah, yes. Whoa, look. There it is. Let's all look at the green screen. Man, it sure is there. Worf, hand me my light saber.
Worf: Uh, Captain...
(Picard stands, appears unbalanced, maybe intoxicated)
Picard: I'm beaming aboard that ship! I'll bitch slap every last one of them!
(He runs at the view screen with a howl, then bounces violently off of it)
The other problem I have with it is the cursing, especially by Patrick Stewart's character. Not your standard curse words which normally constitute cussing; I'm talking about the actual laying down of a curse, like in the olden days. Early in the film he actually turns to the camera and shouts, "A curse on all your houses! May the sword and bloodshed never depart from your family, and may the tumors never depart from your groins!" This is the first time I've actually approved of a family movie receiving an NC-17 rating. Personally, I would have given it an X rating for that scene where Robert DeNiro shoots Harvey Keitel with the jangle pulse.
There is a plot of some kind, involving aliens and/or other dimensions or time travel, or something. At the end, everyone dies. If you like Star Trek, you'll probably like this movie. If you like crap, you will also like this movie. I give it one half star.