The movie adapts a novel Hunter S. Thompson began in the early '60s and published, under Depp's auspices, more than three decades later. A first-person account of the drinking life on a tropical isle in the late 1950s, its protagonists are mainly employees of an undercapitalized English-language daily in San Juan; their perpetually soused attitude is less Beat than Lost Generation, though written (or rewritten) with a heedless hedonism that anticipates the addled excesses of the high '60s.
As the writer-director of the 1987 comedy Withnail and I (a fondly remembered cult film in which a drug-befuddled pair of upper-class degenerates stagger through Swinging London's twilight debris), Robinson would seem uniquely suited to handle the triumphalist disorder of the Thompson worldview. Unfortunately, just as The Rum Diary was conceived too early in Thompson's career for maximum oomph, Robinson's long-germinating, and for several years shelved, adaptation arrives too late in the career of the filmmaker and his star — the bacchanal is weirdly elegiac, as though once meant to be a new Hollywood vehicle for the young Elliott Gould.
The party gets underway with Thompson's alter ego Kemp (played by Thompson's other alter ego Depp) coming to consciousness, having raided the minibar in a dark, trashed hotel room overlooking a glorious beach — his bleary disorientation accentuated by the small plane that flies by with the unfurled banner "Puerto Rico Welcomes Union Carbide." Pave paradise — put up a parking lot! Ugly Americans infest the bowling alley; right-wing capitalists plan vulgar resorts on the unspoiled army testing range at Vieques. Newly arrived from New York, Kemp finds an ongoing, never-exactly-explained riot outside the offices of the San Juan Star and a lunatic editor within (Richard Jenkins). Soon his lowlife colleagues, the garrulous, frustrated news photographer Sala (Michael Rispoli) and brain-damaged crime writer Moburg (Giovanni Ribisi), initiate him into a round of bar-hopping and cockfighting that results in an epic trip to the slammer. Still, The Rum Diary could use a shot of the mania that fueled Terry Gilliam's Fear and Loathing in Las Vegas. As deadpan as he is, Depp could use a crazed Benicio Del Toro to complement his cool.
Although nearby Cuba, newly liberated from the imperialist yoke, is the movie's great unmentioned, Robinson adds a dash of politics to the cocktail. Kemp is a would-be journalistic muckraker who sullenly contemplates Vice President Richard Nixon on TV. "How long can the blizzard of insult continue?!" he demands in gonzo wonderment. Turns out to be long enough for Kemp to be recruited to write a smarmy promotional brochure by a smooth American ex-journalist Sanderson (Aaron Eckhart), shacked up with the captivating Connecticut wild child Chenault (Amber Heard). "This place is a sea of money," is Sanderson's siren song, but Chenault, who charmingly goads Kemp into driving his shiny new Corvette off a dock, is the siren.
As in Thompson's readable but hardly revelatory novel, the narrative reaches its climax at Carnival on St. Thomas with Kemp fallen off the wagon and Chenault casting her spell on a juke joint of drunken mob revelry. Unfortunately the movie soldiers on. Like an emissary from the future, Moburg shows up with an unnamed super drug that, administered as eye drops, gets Sala and Kemp stoned and wildly hallucinating. As though watching an outtake from Fear and Loathing, Kemp sees Sala flexing a fearsome facial appendage: "Your tongue is like an accusatory giblet!" Less convincing is Kemp's resolution to become an honest reporter — never mind that the Star seems to be on the verge of folding — and the fake happy ending that provides a cheerful précis of Kemp and Chenault's subsequent life back in the states.
The Rum Diary has plenty of insolent patter and pungent background clutter; Robinson is good on sweaty, sodden mise-en-scène and elaborately grubby tropical torpor, but he never quite gets the giddy velocity of a what-the-fuck bender. Truth to tell, The Rum Diary is actually more of a light morning-after hangover — it won't leave you with a headache.