I saw "Tropic Thunder" at a screening with about two dozen twenty-something-year-olds, mostly men, who laughed and laughed at just about every scene of the film, while I was trying to remember if I laughed at all. Well, yes, I did, once. This is a film within a film, and when Ben Stiller, who plays the lead actor in it, picks up the head of the film's director after it's been blown off by an old land mine and thinks it's a prop and starts licking at it, yes I laughed. You may say why, but the fact is that I always laugh at anything gross. This was gross and it was funny. And I laughed at Matthew McConaughey as Stiller's agent, probably the best performance in the film. But the rest of it?

Let me start all over again. I know "Tropic Thunder" is being picketed by people who are concerned that the film keeps saying 'retard.' Okay, I understand; it's like saying 'Nigger.' We're not supposed to say it and we don't anymore, unless you're planning not to vote for Obama. Fine. We've grown up and I'm glad - and the use of the word 'retard' in the film is - with one exception - no more than an adolescent attempt at humor. And that exception happens to be unforgivable: there is one one-second shot in the movie that should never have been allowed to stay in. It is a shot of Matthew McConaughey with what is apparently his own Down Syndrome child, but the context of that one second shot is enough to destroy the film. Yes, I know this is supposed to be a parody of Hollywood and all its bizarre rituals, and God knows there are plenty of them. But how they let that shot go by is beyond me.

Stiller, who directed as well as starring and helping to write it- and that was a big mistake, because he has no idea of where to place his camera to make a comic point - Stiller plays Tugg Speedman, a former number one at the box office who's had a whole series of flops until now, including one dreadful weepie called "Simple Jack," about a retarded man who talks to animals; now "Tropic Thunder" is going to reinvigorate his career, because it's the story of a group of soldiers in Vietnam who go on a suicidal mission to rescue one man. Yes, shades of "Apocalypse Now."

The mission consists of Stiller, and Robert Downey, Jr. as an Australian actor who's already won five Academy Awards but now insists on acting in blackface as an African-American and won't get out of character, and Jack Black as a heroin addict who used to star in a television series about a family that farts all the time; plus one actual African-American and one white guy with glasses.

They think that their whole jungle area has already been set up with cameras, so that anything they do will actually go into the film itself, and that by following the script they will always be seen on some hidden camera, but in fact the whole film crew is looking for the now-deceased director, then the group loses their way and ends up in Laos, where they run into a huge heroin operation that's run by a 10-year-old boy. Which probably sounded funnier at the script meeting than it plays out on screen.

In fact, most of the film must have cracked everybody up at the studio - it just didn't work for me. Oh - did I mention that an unrecognizable Tom Cruise plays Les Grossman, the studio head? He's good, and authentic, but just not funny.