Patrick Wilson, left, portrays Nite Owl II, Malin Akerman, centre, is Silk Spectre II and Jackie Earle Haley plays Rorschach in the new film version of the graphic novel Watchmen. (Warner Bros.)

Director Zack Snyder, who dared to turn the acclaimed graphic novel Watchmen into a film, better watch his back. Even though his decent adaptation is unflaggingly fawning and loyal to the sacred text — too loyal, at times — fan boys (and girls) are still going to pelt him with batteries and old software manuals for all he got wrong. That’s the thing about adapting a cult hit for a mainstream audience: insiders are inherently disappointed because they don’t want to share the goods, and outsiders are bewildered because they don’t know the lexicon. Though he may still have fans in the Spartan community for the homoerotic bloodbath 300, Snyder should probably avoid comic book stores and message boards for the next six months.

As far as hideously expensive, earnest graphic novel adaptations go, Watchmen is a pretty good time.

But in fact, as far as hideously expensive, epistemologically earnest graphic novel adaptations go, Watchmen is a pretty good time. Snyder launches the film with a lengthy, whoop-worthy sequence that compresses a convoluted backstory into a perfect mini-movie of tableaus. The characters are arranged into a series of stylized portraits reminiscent of Jeff Wall’s photographs, and the whole ride is set to Bob Dylan’s The Times They are A-Changin’, a predictable choice with surprising momentum. We zoom through the mid-20^th century on a parallel Earth where the Second World War ends, the ’60s groove by and a gigantic nuclear blue guy (Billy Crudup, resembling an anemic reject from the Blue Man Group who enlisted a really awesome personal trainer) wins the Vietnam War for the U.S. Blue is a physicist who suffered a nasty radiation accident and became Dr. Manhattan, one of a group of brooding masked avengers known as the Watchmen.

In New York circa 1985, Richard Nixon is serving his third term as president and America and the Soviet Union are on the cusp of nuclear war. Paranoia reigns and “masks” are outlawed, so the Watchmen have dissipated. Dr. Manhattan and Bowie-ish gazillionaire Ozymandias (Matthew Goode) are trying to develop an alternative fuel source for the planet to stave off a global showdown over oil. (To the grade nines out there: this is called allegory.) Nite Owl II (Patrick Wilson) has gone soft, with a belly that stresses the buttons of his cardigan, while his beaky superhero suit gathers dust in the basement. He has an eye on Dr. Manhattan’s lady friend, Silk Spectre II, who goes by the more terrifying name “Laurie” (Malin Akerman). She’s yet another blank female superhero playing backup singer to the boys, this time in latex aerobics gear.

The handsome couple’s romantic optimism is unusual amongst this group of misanthropes and oddballs. (Anti-heroism still seems to pass as craaaaazy “subversion” in comic book circles, but at this stage, an unconflicted superhero would be truly radical.) The biggest grumbler is Rorschach (Jackie Earle Haley), who metes out his own bloody street justice from under a gauzy mask of undulating inkblots. He shares Travis Bickle’s contempt for street scum (though he doesn’t drive) and has a love of purple prose that serves as the film’s narration: “This awful city screams like an abattoir of retarded children.” Such a Mickey Spillane-in-the-schoolyard observation might have worked in the entirely fantastic cartoon world, but it’s really awkward when it’s rendered in a human voice. Still, Rorschach is the most vigorous force in the film, taking it upon himself to carve up child rapists and stave off the population of an entire maximum-security prison.

Matthew Goode, left, is Ozymandias and Jeffrey Dean Morgan plays the Comedian in Watchmen. (Warner Bros.)

Haley has an unnerving ferocity in that compact body as he storms the city trying to find out who’s picking off the Watchmen. The Comedian (Jeffrey Dean Morgan), their most savage member — a rapist who shot his pregnant Vietnamese girlfriend because he could — has been thrown out a window. But by whom?

That mystery is really just a laundry line on which to peg a series of musings about the brutish nature of mankind, God’s grand design, moral relativism and other chatter that makes an audience feel better about the violent turn-on at the story’s core. (Still, no one dares utter the most important philosophical question of all time: Why do female superheroes have to fight in high heels? How about a sassy metallic flat?)

Watchmen is a gruesome film, and entirely inappropriate for children, not so much because of the casual penis parade — Dr. Manhattan’s codpiece is often at the drycleaners — but the relentless hacking, slashing and splattering. There is also a sex scene that’s semi-explicit, which is a nice change from the hypocrisy of most films in this genre, where violence is full-on and sex is prudishly limited to nerd-pleasing cleavage close-ups. The mere existence of the scene (set, rather wittily, to Leonard Cohen’s Hallelujah) underlines that Watchmen, for all its ontological pondering, is supposed to be kind of pleasurable. This alone distinguishes it from the humourless assault of The Dark Knight, which was many things, but fun wasn’t one of them. Watchmen is also visually superior to that overrated burden, because it’s not just shot stylishly, but clearly, as if Snyder actually cares whether his audience can follow the story.

Which it will — mostly — even though the film is overstuffed with characters and a litany of origin stories, a sign that Snyder feared offending purists by pruning. And in the final third of its cruel length (nearly three hours), the film succumbs to inevitable, hilarious self-importance. Any plot that culminates at an Antarctic hideout where a mad genius walks the halls with an animal at his side — in this case, a sabre-toothed tiger-ish fella — is, you know, silly.

But when it comes to comic-book movies — even when the comic book has been elevated to the category of “graphic novel” — I’ll take silly over pretentious. Alan Moore, the grumbly genius who created Watchmen (drawn by Dave Gibbons), has taken his name off the film, as he did with previous adaptation flops like The League of Extraordinary Gentlemen and V for Vendetta. Maybe he’s a little persnickety. Watchmen isn’t perfect, or even that relevant — that Cold War thing actually worked out OK — but it’s a joyride in parts, with pop pastiche and atmosphere to spare, just like the book. Fan boys may feel differently.

Hey, Snyder — duck!

Watchmen opens March 6.

Katrina Onstad is the film columnist for CBCNews.ca.