And nobody ever, ever bursts into song in "King Arthur" — though it might be sort of fun if they did, if only to break up the intensity of the battle scenes, and to brighten the literal and thematic sludge through which the warriors valiantly slog.

All this movie shares with the King Arthur you're familiar with is a name.

Supposedly, it's the story behind the legend — set in the Dark Ages, not the Middle Ages — with the half-Roman, half-British Arthur (Clive Owen) leading a seemingly outmatched band of Sarmatian knights, including his best friend, Lancelot (Ioan Gruffudd), against the invading Saxons.

Although he's torn ethnically and struggles to maintain his religious faith in the face of cynicism and hypocrisy, Arthur somehow finds time to get it on with Guinevere (Keira Knightley), who is not the fragile flower you've seen before, but a buff warrior princess who's deadly with a bow and arrow.

The real story behind the story-behind-the-story, though, is that this is a Jerry Bruckheimer movie, striving desperately to be taken seriously.

"King Arthur" was directed by Antoine Fuqua, and resembles his earlier film "Training Day" in the visceral, gritty nature of its battles. It was written by David Franzoni, and resembles his earlier film "Gladiator" in its manly-manness and its obsession for historical lore.

If "King Arthur" brings to mind any previous film that Bruckheimer produced, it's "Black Hawk Down." Both share the same cinematographer, Slawomir Idziak, and at times share a similarly bleached-out, grainy look. It's an especially effective aesthetic when Arthur and his heavily armed posse are trekking on horseback through the snow, and on a cracking frozen lake, where the film's most suspenseful brawl occurs.

For all its attempts at innovation, though, "King Arthur" falls back on the hackneyed "one last mission" idea. Arthur, Lancelot, the brutish Bors (Ray Winstone) and the rest of the knights — who aren't nearly so well characterized — must rescue a Roman nobleman and his family, which includes a son who's a favorite of the pope.

Their assignment takes them north as Saxon forces are spreading under the leadership of Cerdic (Stellan Skarsgard), whose long hair and messy, braided beard make him look like a redheaded Rob Zombie. His men, meanwhile, who are heavily garbed in leather and fur, seem to have stepped off the runway of a Sean John fashion show.

The point being that despite its pretenses otherwise, this is still a big summer action movie, full of cliches and sexed-up details.

It's hard to believe Guinevere actually chose her own battle gear, which consists of little more than a couple of brown leather belts strapped across her chest. Granted, the movie takes place far prior to the advent of the jog bra, but this is a woman who apparently managed to find lipstick and eye liner in the forest. She should have been resourceful enough to craft more protective clothing during the dead of winter, as her male counterparts did.

But Knightley continues to prove herself a versatile young actress: She can do comedy ("Pirates of the Caribbean: The Curse of the Black Pearl"), she can do romance ("Love Actually"), she can be young and fresh in a girl power movie ("Bend It Like Beckham"). Here, she just plain kicks butt.

Winstone, so excellent in "Sexy Beast," here provides sporadic, much-needed comic relief as a knight whose girlfriend has given birth to so many of their children, they've assigned them numbers rather than names.

They "mean something to me," Bors says during a rare moment of introspection. "Especially No. 3 — he's a good fighter."

The best fighter of all, though, is Arthur himself. And Owen, so suave in the excellent noir hit "Croupier," provides weight, intelligence and heroism to go along with his dark good looks.

He deserves a movie more worthy of his innate magnetism and strength — and following "King Arthur," he should be able to find such a holy grail of roles.