The Rum Diary is something like the secret origin of Hunter S. Thompson. Set in Puerto Rico in 1960, it shows the young reporter getting his sea legs as a burgeoning gonzo journalist. Johnny Depp stars as Paul Kemp, a Thompson avatar, fresh faced and with a full head of hair, years away from the debauchery of Fear and Loathing in Las Vegas. Given that Depp played the man in Terry Gilliam's adaptation of that more famous tome means the comparisons are all but inevitable. Probably a little desired, as well. Gilliam's movie has become somewhat of a cult favorite, and I am sure the makers of The Rum Diary would call this an official prequel if they could.

Naturally, since this story takes place prior to Thompson's discovery of substances harder than alcohol--indeed, The Rum Diary shows us his first encounter with what is presumably LSD--it is tamer in nature than Thompson's Vegas adventure, and also more conventional in its plotting. Kemp lands in Puerto Rico with a falsified resume and several stillborn novels. There, he works for the editor of a failing paper, played with considerable rancid charisma by Richard Jenkins (The Visitor). This assignment is the equivalent of the most remote outpost, the worst shift on a work force that would otherwise reject the misfits who take it. Amongst Kemp's new compatriots are a besotted photographer (Michael Rispoli, Kick-Ass) and a Nazi-loving, degenerate reporter (Giovanni Ribisi, Avatar), who resembles the bottom of the barrel that Kemp himself may eventually end up in.

Also in Kemp's new social circle is a slick wheeler and dealer named Sanderson (Aaron Eckhart, The Dark Knight). He brings Kemp into his business deal to take over a neighboring island and turn it into a resort. Kemp will write the PR for the venture and pass it off as news. Or so is the plan. The writer is more interested in Sanderson's alluring, fun-loving girlfriend than he is any under-the-table business deal. Chenault is played by Amber Heard (Drive Angry), so I can't say that I blame him. Heard struggles to make something out of what is essentially a cliché role--the bruised love interest that the boys posture over--but damn, she sure is pretty. It's reason enough to believe that Kemp would ignore common sense and fail to resist her, but he's a man who has trouble ignoring temptation in general. The rum calls to him and colors all he sees. Oh, there is lots and lots of rum.

The legend is that The Rum Diary was a lost manuscript gathering dust in Hunter S. Thompson's house when Depp spotted it and urged the author to publish. The actor has been shepherding the film project for most of the 21st Century, and he's credited with choosing Bruce Robinson to direct. That Robinson stepped behind the camera for this should give a charge to fans of his black comedies Withnail and I and How to Get Ahead in Advertising. The writer/director hasn't made a feature since his 1992 flop Jennifer Eight. Fans of Withnail will see a comparable booze-soaked relationship to that film's title characters in the pair of Depp and Rispoli. Here are two aimless gentlemen passing the time by imbibing as much as possible. The part of Sala the photographer is a breakthrough moment for Rispoli. He is hilarious as the cockfighting cynic, and far more grounded than his co-star, whose performances increasingly rely on caricature. Don't get me wrong, I enjoy watching Johnny Depp on screen, but Captain Jack Sparrow isn't his only recurring role that depends heavily on shtick. His portrayal of Kemp is all mannerisms, both physical and vocal, and lacks any deeper feeling. It's a far cry from his take on Ed Wood, where the funny voice and manic pantomime was window dressing for a surprising vulnerability. Frankly, I think he gave Tim Burton something remarkable in that film that his frequent collaborator has failed to get out of him since.

Maybe this wouldn't be as noticeable if The Rum Diary had the visual whimsy or the narcotic mayhem of Fear and Loathing. Gilliam gave Depp a twisted groove in which to work his magic, and Robinson's adaptation is far more ordinary. It builds up a lot of narrative complications by using the economic invasion of Puerto Rico to raise a house of cards that an increasingly righteous Kemp can topple, but the meatier aspects of this social brutality aren't fully engaged by the writing. While the movie ends with a rage-filled Kemp vowing to use words to destroy "bastards" wherever he may find them, The Rum Diary's third act treats Kemp's exposé on Sanderson and his greedy cronies as cursory. The real motivation seems to be Kemp's desire to see Chenault naked. And don't even get me started on the macho chest beating that goes on during Carnaval, or the disturbing scene where the white men abandon their blonde trophy to the locals, who are portrayed as little more than dark-skinned savages.

I feel like I am nitpicking The Rum Diary to death and failing to communicate the fact that I actually enjoyed the movie. It's often quite funny and the occasional snatches of voiceover from Kemp's diary provide some welcome seasoning that draws out some of the deeper meaning of the material. It's a fun film to watch, if not entirely engaging. Perhaps that's what frustrates me most, it seems like it's right about there and all it would have taken was a few more adventurous choices to make a cracking motion picture. Bruce Robinson does enough to stake his own claim and make The Rum Diary work as a solo endeavor, so perhaps it's to his detriment that there has been so much effort put into making sure we spend about thinking about the film it prequelizes. The Rum Diary may set the mythos spinning toward dizzy heights, but it also reminds us that we aren't quite there yet.

Jamie S. Rich is a novelist and comic book writer. He is best known for his collaborations with Joelle Jones, including the hardboiled crime comic book You Have Killed Me, the challenging romance 12 Reasons Why I Love Her, and the 2007 prose novel Have You Seen the Horizon Lately?, for which Jones did the cover. All three were published by Oni Press. His most recent projects include the futuristic romance A Boy and a Girl with Natalie Nourigat; Archer Coe and the Thousand Natural Shocks, a loopy crime tale drawn by Dan Christensen; and the horror miniseries Madame Frankenstein, a collaboration with Megan Levens. Follow Rich's blog at Confessions123.com.