Serenity

There's a reason the Cream of the Crop on Rotten Tomatoes gave Serenity an 86%. Several of the people I know have said, "Isn't it just like the series? I didn't watch the series? Shouldn't I have watched the series?" (the series being Firefly). There's no need to watch the series before the movie (though I'd recommend watching the series for its own sake) - the movie stands on its own and its wonderful. There's a reason Joss Whedon has been nominated for an Oscar and an Emmy, and this movie reeks of a great writer and capable director who's finally had enough money lobbed at him to create a worthwhile piece of film. Great characters with intricate motives and personalities, lots of action, and neatly tied together from beginning to end. If you sat through the Matrix III or Fantastic 4, you deserve the science fiction treat that is this movie.