'Tropic Thunder' a hit-and-miss action comedy

"Tropic Thunder" promises a nonstop hailstorm of ribald comedy, but it only delivers scattered cloudbursts.

Starring and directing, as well as assisting with the screenplay, Ben Stiller is out to satire Hollywood and all its hokey conventions. With his comedic frag grenades, Stiller lobs bombs at egotistical method actors, standup comics who make detestable gross-out comedies and self-obsessed filmmakers who indulge their personal quirks at the expense of their colleagues.

The film starts with an ingenious prologue: trailers for made-up movies featuring each of the characters in the movie-within-a-movie. Aussie Kirk Lazarus (Robert Downey Jr.) pops up in a thematic knockoff of "Brokeback Mountain," fading action star Tugg Speedman (Stiller) languishes in the umpteenth sequel to one of his franchises and bloated comic Jeff Portnoy (Jack Black) stars in several simultaneous roles (a la Eddie Murphy) in a flatulence-inspired comedy. Also, rapper Alpa Chino (Brandon T. Jackson) gets jiggy in a commercial promoting his energy drink, called Booty Sweat.

The movie proper starts in Southeast Asia, on the set of the mega-budget, Vietnam-conflict rehash titled "Tropic Thunder." In-over-his-head British director Damien Cockburn (Steve Coogan) can't control his wily cast and Speedman -- coming off a critical and commercial failure in an attempt to play a mentally disabled character in an art film -- is intimidated by Lazarus, who has undergone a pigment-changing procedure to play a black soldier.

The astoundingly talented Downey, continuing the recent resurgence he started with "Iron Man," treads perilously close to the territory of race-baiting offensiveness but keeps his clueless thespian just innocently likable enough to elicit chuckles rather than groans. Refusing to break character even when the camera stops rolling, Lazarus spins a wicked web of dated stereotypes that alienate him from everyone else, particularly Chino. So deep into the character is Downey that when Lazarus stops his act, he's got an Australian accent.

If only the tepid script and the supporting performances were up to Downey's standard. Stiller is at his best as a weak-willed Everyman, and just isn't the right casting choice for an action hero. Stiller would have done better to call up Jean-Claude Van Damme or Steven Seagal -- both of whom could surely use the work -- and given the role some true meat and authenticity.

At the insistence of the burly war hero (Nick Nolte) who wrote the book on which the film is based, the director takes the production to a real war zone without telling the actors what's going on. As Lazarus and Speedman struggle for command, basing their judgments on battle techniques they've learned from movies, the squad marches into combat, assuming the bullets they're firing are blanks and the men they're fighting are extras.

There's potential here for a memorable satire, but jarring tonal shifts edge the comedy off-track. Stiller can't seem to decide whether he wants to make a comedic send-up of action films or a war thriller that succeeds on its own merits. The result is a jumbled mess that has you laughing in spurts, then hanging back in your seat waiting through minutes of dead space filled with nonsensical explosions.

Tom Cruise steals what's left of the film with an out-of-nowhere performance as a bald, obscenity-spewing studio head with a penchant for hip-hop dancing. You half wonder what drew Cruise to the role, but it becomes pretty obvious -- had Cruise declined the part, Stiller probably would have mocked him mercilessly in the movie.

Stiller fanatics will eat "Tropic Thunder" up, but those lured in by the hype will be crushed, walking out of the theater afterward in a buzz of thunderous grumbling.

2.5 stars out of 4

Rated: R. Pervasive language including sexual references, violent content and drug material.

Family call: Too vulgar for kids.

Running time: 107 minutes.

(Pvillarreal(at)azstarnet.com.)

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