A MOVIE WHICH PROVES THERE'S NOTHING TIVO CAN'T DO: Tropic Thunder is the funniest thing Ben Stiller has done since Zoolander -- a long time, indeed, but quite worth it. Does the whole thing cohere? No. I still have no idea when the actors realized that it wasn't still a movie, or why Downey's face magically seemed lighter in the main late sequence, and still don't understand why (between this and Pineapple Express) Asian Drug Lords became this year's all-purpose menace ... but none of it matters, because the gags are good. Really good. Not just the Tom Cruise stuff -- which, yeah, is that good, but especially the Downey.
I will agree with Our Friend Dan Fienberg that the film doesn't say anything new, and that there's a darker, more challenging movie that could have been made with this premise. And as The Wife noted, there's not one real female role in the film. But, end of the day, it's funny enough. More than. If you go for broad humor, that is. And Downey.
[Speaking of which, I take Dave Itzkoff's thinkpiece on gross humor as an implicit correction, insofar as it refers to an incident in There's Something About Mary as "the protagonist’s genitals caught in the zipper of his pants".]
I realize that I haven't really described any of the gags. I shouldn't. You know the setup. You know who's in the movie. If you thought you might want to see the movie, then, yes, see the movie. And let me not spoil a single thing here.