There is a reason why in most films different people take on the roles of the writer, director,  and the lead actor: Rarely is one and the same person equally good at all these jobs.  Tropic Thunder stars Ben Stiller, and is written and directed by Ben Stiller. That was a mistake. When I saw the trailer a few weeks ago, my hopes soared. Perhaps Tropic Thunder was going to be as funny as There is something about Mary. Far from it, the new Ben Stiller vehicle only provokes a few laughs. The story (a film crew making war movie in Vietnam comes under real attack) is rather weak, a mumble jumble of ideas that Stiller had over the years. The best part of the movie was Tom Cruise, who plays a slimy, foul-mouthed, overly hairy Hollywood producer. Cruise steals the show from Stiller, even though he only played a minor character, in a sideline of film. I am not going to see another film written and directed by Stiller any time soon.