Fear-of-flying cinemagoers might want to skip Denzel Washington’s new film Flight, a dramatic detour from veteran director Robert Zemeckis, who has spent the last decade fiddling with performance capture technology in The Polar Bear Express (2004), Beowulf (2007) and A Christmas Carol (2009).

There are two good reasons: 1) it opens with a spectacularly visceral white knuckle plane crash sequence and 2) plants the unsettling idea that the next time viewers travel by flight, the person responsible for steering them through the skies might be three sheets to the wind.

The two-time Oscar-winning Washington has racked up another Academy nom for Flight’s Whip Whitaker, a protagonist more than a mite partial to a visit from Mr Booze and his mind-altering brethren. Setting the tone for a distinctly non-Zemeckis-like plunge down a druggy rabbit hole, Flight’s opening scene wouldn’t look out of place in something as bat shit crazy as Fear and Loathing in Las Vegas (1998).

An alarm clock next to a glass of dark spirits rings at 7:14am; a naked woman emerges from a hotel room bed where Washington, looking flabbier than usual, wakes up, answers his phone and drinks the remains of a beer bottle opened hours ago. The woman passes him a joint. Whitaker mumbles “I feel a little light headed. Shoulda ate something” (one of the first lines of dialogue in Fear and Loathing is “I feel a bit lightheaded. Maybe you should drive”). Whitaker snorts a fat line of cocaine from a bedside table and —

He’s feeling alright. That’s the song playing as a schmickly dressed Whitaker, in aviators and commercial pilot uniform, struts down a hotel corridor wheeling his travel bag behind him. On the plane he orders “coffee, black, lots of sugar and a couple of aspirins” then inhales oxygen. In the spirit of the generous ‘drugs for all’ fiend, he asks his co-pilot: “want a hit?”

The audience watch anxiously, tossing up what is going to go wrong, when, and on what level. But the point is made as soon as Whitaker is in uniform — pushing aside the fact that he drinks three bottles of vodka in the cockpit — that he acts, to use a phrase from the Thompson lexicon, like a god damn professional: cool, focused and armed with a droll sense of humour. Against heavy weather Whitaker launches the plane, noting that “there’s nothing like a little 30 knott wind to exercise the old sphincter muscles.” After unexpectedly deviating from course to blast through inclement weather, his co-pilot yelps “oh lord,” to which he responds “can’t help you now, brother.”

But the shit really hits the fan when Whitaker is forced to crash land the plane due to a mechanical error. The technique the semi-sloshed pilot uses is galling and inspired: he flips the plane, re-aligns it, and saves 96 out of 102 people on board. Later in the film a lawyer for the pilot’s union, played by Don Cheadle, balances disdain for his actions with praise for his skill and heroism. You were flying a plane while sozzled, Cheadle says, but sober or not (other pilots were tested in subsequent simulations) nobody could have done it better.

The easy way out for Zemeckis and screenwriter John Gatins would have been to write their protagonist drunk and high on the plane (which he was) and have him crash it because of his altered state of consciousness — a horrible  black and white wake up call for a life spent gorging on uppers and downers.

Instead they push the following point: not only was it not Whitaker’s fault that the plane crashed, it was his skill that saved lives. This raises some interesting questions. Would you want a drunk pilot attempting to steer to you safety? And would you want anyone other than this pilot?

The story is set up so viewers answer no to the first question but pause to contemplate the second. The resulting film is not about the investigation of the crash, per se, but a study of an alcoholic, inside the framework of a surprisingly nuanced look at drug use and addiction.

“In one outstanding sequence, Whitaker’s alcoholism almost literally comes knocking on his door, leading to a simple image more rousing than the plane crash”

Alcohol, our most socially acceptable recreational drug, is also, in Flight, depicted as by far the most dangerous. Not because the film turns a blind eye to other substances — Whitaker’s romantic interest Nicole (Kelly Reilly) is a smack addict, and ODs early on — but because it’s so intensely focused on one character.

Whitaker’s greatest predilection is alcohol and, naturally, it’s available everywhere. Treading similar ground to  Billy Wilder’s exasperatingly cautionary The Lost Weekend (1945), in which Ray Milland plays a desperate drunk finding and hiding drops wherever he can (lamp fittings, under the coach, from the bar down the road, etc) Whitaker encounters booze everywhere. Nicole must visit a scungy porn set to get her fix, and handle propositions from her dealer, but Whitaker grabs bottles from hotels, planes, bars, kitchens, service stations, his family cabin in the sticks…

In one outstanding sequence, Whitaker’s alcoholism almost literally comes knocking on his door, leading to a simple image more rousing than the plane crash: a small bottle of vodka sitting on top a bar fridge. Throughout his years as a frothy middle of the road Hollywood director, and now as a doyen of technical whizbangery, Robert Zemeckis never landed a blow like this.

Flight’s approach to capturing drug use is  fascinating, and not just for a Hollywood film. Gatins’ screenplay comes close to celebrating cocaine as the ultimate ‘leveler’ capable of transforming a slurring drinker into a straight-thinker. “Shit, I’m back!” a previously woozy Whitaker exclaims after hoovering down a line supplied by his dealer, played by John Goodman in hilarious Samoan attorney mode. But Gatins goes further, suggesting that if his groggy protag didn’t get the buzz from coke at the start of the film, he might not have had the gumption to flip the plane.

Compare this kind of moral complexity to Darren Aronofsky’s acclaimed drug horror/drama Requiem for a Dream (2000), a film far more black and white than its appreciators may care to admit. Aronofsky’s tale of three junkies and one prescription meds addict plays like a propaganda film, its four principal characters bottoming out into hell holes of comeuppance. One has his arm sawed off; one sweats through comedown hell in prison; one commits disgusting sex acts for money; the other gets turned into a vegetable c/o electric shock therapy.

In Flight Zemekis and co. have achieved something braver than the familiar “drugs are bad mmmk” chestnut, creating one of Hollywood’s most vivid portrayals of a functional alcoholic character, and asking us not to judge him not by his addiction but (without giving away the film’s ending) on wider moral issues.

“Washington’s portrayal of a self-aware alcoholic who broadly understands what is happening to him but is unwilling or unable to change it is a terrific turn of acting”

Other celebrated films featuring memorable portrayals of booze hounds such as Harvey (1952), The Verdict (1982), Barfly (1987), Leaving Las Vegas (1995) and House of Sand and Fog (2003) have richly textured drunks — though not of the highly functional kind — and almost always hover on the border of stereotype. They are respectively about a man followed around by a seven foot imaginary rabbit, a lawyer who has drunk his business and credibility into oblivion, a rough-as-guts writer constantly embroiled in altercations, a screenwriter incapable of holding a job and a homeless woman battling suicidal tendencies.

Washington’s portrayal of a self-aware alcoholic who broadly understands what is happening to him but is unwilling or unable to change it is a terrific turn of acting, a character so easy to spill into caricature: slurry words here, random abuse there (Washington’s performance only embraces the “mumble like a drunken idiot and collapse on the floor” shorthand once). Whitaker is in virtually every scene in the film and of those scenes he is drunk for the vast majority. When he isn’t drunk he’s hangover and/or perturbed. In other words he is never “normal”.

The most important question his character is asked isn’t about whether he drank on the plane or what happened the night before the crash. It’s one posed by his son: “who are you?” And by inference: how has alcohol changed you?

Asked by The Guardian what the film says about saving ourselves, Zemeckis responded: “it’s not so easy.” Nor is it easy, after plunging audiences so deeply and unflinchingly into the heart of a character like Whitaker, to sell the idea that they are capable of redeeming themselves.

Flight isn’t preachy enough to be a film about redemption. Perhaps it’s better described as a story about how it can take the equivalent of a plane crash to rouse a person from drug addiction, and even then that might not be enough. That Zemeckis keeps the door open to the possibility of a reformed life for his soiled subject feeds an important extension to the idea of Whitaker as the ultimate high-functioning alcoholic: a person who, in addition to saving dozens of people while tanked, must also be somehow capable of saving himself.

To arrive at that point the film’s conclusion shifts gears a little too quickly, depleting some of the goodwill it worked so hard for — though there is plenty left in the bank. At the same time Zemeckis adds complexity by deploying a subtle acknowledgement that past vices have a way of flying back into our lives. It’s a point made deftly, like the bottle of vodka above the mini fridge. This time using a single, final sound effect.

Flight’s Australian theatrical release date: January 31, 2013.