Tropic Thunder (2008)

First things first: if Robert Downey Jr. ever disappears from cinema again, I will be one unhappy chappy. Despite getting third billing behind Jack Black and Ben Stiller (who is also credited here with co-writing, co-producing and directing), Downey owns Tropic Thunder. He plays an Australian actor who gets so involved in his roles that he undergoes major pigmentation surgery in order to play a black man; it's a unique hook for a character and Downey is incredibly convincing in selling it. Like Heath Ledger's scene-stealing supporting role in The Dark Knight, the hype for Downey in Tropic Thunder is justified. His Oscar nomination is every bit as worthy as Ledger's.

Downey is part of a motley crew of actors abandoned in the Vietnamese forest by their director (an underused Steve Coogan) in an attempt to reign in an over-budget and behind-schedule war film. When the actors come across a gang of real-life drug runners, they debate whether the encounter is all part of the script and a series of fairly amusing misunderstandings ensues.

It's a high-concept comedy that, despite a crowd-pleasing cast of Stiller, Black, Downey, Coogan, Nick Nolte, Matthew McConaughey, and an unrecognisable Tom Cruise in an extended cameo, manages to be pretty offensive on a number of levels; this isn't family fare. The key is to remember that while Tropic Thunder seems to poke fun at taboo subjects such as disabilities, homosexuality and war, it's mostly taking sly digs at the representation of these subjects in Hollywood.

In fact, this is when Tropic Thunder is at its best: parodying Hollywood. Preceded by a handful of superb mock trailers (including one which hilariously juxtaposes Downey's "five-time Academy Award winner Kirk Lazarus" with "MTV Movie Award Best Kiss winner Tobey Maguire", who cameos as himself), Tropic Thunder opens with an extended action sequence from the film-within-a-film. It's a genuinely amusing take on the war genre: the camera lingers for far too long on the gore and dramatic sequences are way overplayed. When Tropic Thunder takes on the Hollywood machine – from Oscar-grabbing fare to blockbuster sequels – it's on fine form.

Unfortunately, once the cast realises the film they're shooting isn't a film at all, the satire makes way for average gags and the movie ceases to be particularly funny. Downey remains captivating, the locations look terrific (Hawaii doubles for Vietnam) and Tom Cruise's cameo stays shocking right until the credits roll (if only because it's Tom Cruise), but without the Hollywood mickey-taking, Tropic Thunder is just a slightly-above-average big-budget comedy.