Shaggy-dog story is casually cheeky and frankly celebratory.

A shaggy-dog story based on stranger-than-fiction fact, Bernard Rose’s “Mr. Nice” is casually cheeky and frankly celebratory as it charts the improbable rise and inevitable fall of Howard Marks, an amiable bloke from the valleys of South Wales who controlled a sizable portion of the world’s hashish trade in the 1970s and ’80s. Based on Marks’ bestselling autobiography, this mildly amusing but overly discursive biopic likely will play best in those international markets where its subject — freed from U.S. incarceration in 1995 — remains enough of a celebrity to command large audiences with a one-man stage show.

Rose brackets “Mr. Nice” with glimpses of Marks (Rhys Ifans) dryly addressing an adoring audience at some cavernous theater, indicating that we should view the pic as an illustrated version of a rambling monologue. That impression is reinforced as Ifans’ Marks serves as narrator throughout, providing a p.o.v. that, while probably not totally reliable, helps make a potentially off-putting character ingratiating.

With his snarky wit, droll demeanor and shaggy coiffure, Ifans often seems to be channeling George Harrison as he shambles through the highlights of Marks’ life, following him from his salad days in Wales through his stint at Oxford, where he embraces the drug subculture, and on to his storied career as a drug dealer. For the latter, he never apologizes, explaining early on that a drug dealer is merely someone who sells the dope he can’t consume by himself.

In the world according to “Mr. Nice,” Marks more or less lucked into his vocation. Pic has him cutting short his teaching career — roughly around the same time his wife cuts short their marriage — in order to help a former Oxford classmate smuggle a carload of dope back from Germany. His success provides him entry into the demimonde of drug traffickers — and earns the approval of the beautiful Judy (Chloe Sevigny), who gradually becomes his lover, the mother of his children and, eventually, his wife.

Applying the same smarts and resourcefulness that got him into Oxford, Marks establishes an immensely profitable international smuggling enterprise. He audaciously enlists the aid of a fanatical IRA leader (David Thewlis) to run hashish through Ireland’s Shannon Airport, and exploits a fortuitous contact by another former classmate (Christian McKay, again looking like a young Orson Welles), an MI-5 operate who recruits Marks as a freelance spy.

And when he opts to expand his business to the U.S., Marks finds a ready partner in an eccentric American libertine played — eccentrically, of course — by Crispin Glover.

“Mr. Nice” is a bit fuzzy when it comes to explaining just how Marks rises to the top of his field so easily, even with the MI-5 connection and, evidently, other friends in high places. And while it’s clear he has ready access to dozens of aliases and millions of dollars, it seems borderline-incredible that he’s able to remain free as a fugitive abroad for so many years after jumping bail in the wake of a London arrest.

Ifans does a fine job of keeping Marks likable, if not always sympathetic, even after the unrepentant trafficker plays the equivalent of a “Get Out of Jail Free” card, then fails to take advantage of his second chance. As Judy — actually a composite of two real-life characters — Sevigny is sexy and supportive, but compellingly conveys in a key scene the unbearably high cost of standing by her man.

Thewlis exudes dangerous vibes with sufficient ferocity to give the audience some idea of the stakes involved; as the U.S. narcotics agent obsessed with Marks’ capture, Luis Tosar doesn’t manage quite the same level of menace.

“Mr. Nice” fluctuates between relatively straightforward naturalism — there’s a significant amount of suspense generated during Marks’ early misadventures — and artfully stylized artificiality. Effectively doubling as his own co-editor (with Teresa Font) and director of photography, Rose occasionally uses tinted imagery, obvious rear-screen projections and slow-mo sequences to hint that we’re seeing events though the eyes of a smuggler stoned on his own product.

The mix of visual and narrative styles, while not entirely seamless, is well suited overall for a first-person account by a charming rogue with few regrets about serving hash to millions of satisfied customers. And much like Howard Marks — both the character onscreen and the real person in print and onstage — “Mr. Nice” unabashedly argues for the decriminalization of drug use. So much so, in fact, one can only wonder if anyone involved ever considered titling the pic “Just Say Yes.”

Mr. Nice

U.K.

Production

An Independent (international sales) presentation of an Independent production in association with Prescience and Kanzaman Prods. Produced by Luc Roeg. Executive producers, Michael Robinson, Andrew Orr, Paul Brett, Tim Smith, David Toso, Linda James, James Perkins, Dan Shepherd, Norman Merry. Co-producers, Denise O'Dell, Mark Albela. Directed, written by Bernard Rose, based on the book by Howard Marks.

Crew

Camera (color), Rose; editors, Rose, Teresa Font; music, Philip Glass; production designer, Max Gottlieb; art directors, Tim Dickel, Sonia Aranzabel; costume designer, Caroline Harris; sound, Paddy Owen; associate producers, Philip Herd, Lisa Enos, Denis Pedregosa; assistant director, Joe Geary; casting, Alex Johnson. Reviewed at SXSW Film Festival (Headliners), March 14, 2010. Running time: 120 MIN.

With

Howard Marks - Rhys Ifans Judy Marks - Chloe Sevigny Jim McCann - David Thewlis Craig Lovato - Luis Tosar Ilze - Elsa Pataky Saleem Malik - Omid Djalili Ernie Combs - Crispin Glover Patrick Lane - Jamie Harris Hamilton McMillan - Christian McKay Graham Plinston - Jack Huston
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