About halfway into this Jerry Bruckheimer-Antoine Fuqua take on the Arthurian story, there’s a battle-on-the-ice scene that’s really quite remarkable–not because it’s especially well-staged or exciting (it’s not), but because it has the temerity to crib from not one but two obvious sources. The first, of course, is Eisenstein’s “Alexander Nevsky,” which includes a much more elaborate and brilliantly crafted sequence along similar lines. The other is no less than the Bible: the scene is essentially a crossing-of-the-Red Sea imitation, with frigid weather and ice replacing the Sinai sun and the waters divided by Moses’ staff. After the fleeing horde Arthur and his small band of knights are leading to safety have gingerly traversed the ominously crackling surface of the lake, much of the pursuing army of brutal Saxons crashes (with a little help from the knights’ arrows and axes) through the ice-covered surface into the water and to their doom. It really takes chutzpah for a cheesy picture like “King Arthur” to trash a classic film and the Book of Exodus simultaneously.

But this sequence isn’t particularly offensive as much as it’s characteristic of a picture that sees fit to belittle virtually everything it touches–history, literature and legend–by turning it all into a dank, dreary pseudo-adventure flick without much energy and precious little grandeur. “King Arthur” is an orgy of anachronism in a sea of bad action-movie cliches. The number of historical inaccuracies in this supposed effort to portray the “real” Arthur is enormous, but the number of movies and TV shows from which it lifts its ideas and effects is probably just as large. If you took “The Vikings,” “Braveheart,” “The Seven Samurai,” “Gladiator” and “Xena: Warrior Princess,” tossed them into some infernal cinematic blender and dumped the result onto the screen, it would look very much like this picture.

By itself, of course, the idea of eschewing the high medieval feudal trappings of the traditional Arthurian cycle–the vision, ultimately derived from writers from Geoffrey of Monmouth through Malory, of chivalrous knights seated at the round table of a just and gracious king and engaging in high-minded quests, and of beauteous ladies with whom sometimes furtive romances occurred–in favor of a more “historically” based version of the story isn’t a bad one. David Franzoni situates the story instead in the primitive milieu of fifth century Britain, which is arguably correct–the sole reference to an Arthur in a reasonably contemporary source (ninth century, probably) connects a military leader of that name (or title) with the battle of Mount Badon against the Saxons, which is variously dated between 491 and 518. But around this solitary tidbit of “historical” information Franzoni has constructed an elaborate and, as it turns out, highly derivative scenario. In this telling, Arthur (Clive Owen) is the Roman commander of a small contingent of Sarmatian horsemen–warriors from the east–in the Roman province during the late 460s. He’s also a follower of the British theologian Pelagius, characterized here as a proponent of the ideals of freedom and equality among men. As the story opens, the stalwart band is escorting Bishop Germanius (as the credits call him) to the seat of Roman authority, presumably near the great wall of Hadrian in the north, protecting the prelate against attack from the native army of Picts from the other side of the structure, led by Merlin, here a tribal chieftain. Germanius is supposed to give Arthur’s knights their discharge papers so that they can return home after their stipulated fifteen years’ service, but unexpectedly he requires one final, almost suicidal mission of them: to go north of the wall and rescue a noble Roman family whose son Alecto is a godson of the pope and destined for great things, and who are threatened by an army of invading Saxons. The troupe reluctantly undertakes the assignment, only to find the nobleman they’re saving a vicious and bigoted brute. (Alecto, on the other hand, seems a reasonable young man, who informs Arthur that his idol Pelagius has been executed for heresy back in Rome.) The soldiers nonetheless collect the Romans and the surrounding peasants and lead them southward to the safety of the wall. The Saxons pursue, but the fugitive band eventually reach the border through the aforementioned lake battle stratagem. Arthur, however, decides to remain after the others evacuate and face the Saxons alone. His knights choose to join him, and in a magnificent if costly victory on the plain south of the wall, aided by Merlin’s Pict forces, they defeat the German invaders. Arthur and Guinevere, Merlin’s daughter whom Arthur had rescued from Roman captivity (and who’s since shown herself an archer equal to any man), marry, and Arthur becomes king.

The first thing to note about this scenario is that despite all the intimations of its historicity in the pre-titles and press materials, it represents a degree of invention and gross inaccuracy by Franzoni even greater than that in his script for “Gladiator.” The Romans had in fact evacuated the province of Britain by 410, and the idea that a Roman commander and a group of Sarmatian cavalry would still be assigned there at the end of the fifth century is nonsense. (All that’s really known of the Sarmatians, incidentally, is that after their tribe’s defeat by Marcus Aurelius along the Danube in the second century some of their men were enlisted in the Roman army for service wherever assigned.) In fact, the idea that Hadrian’s wall would still be manned in the 460s is farfetched, and it’s completely absurd that a noble Roman family would be living on a villa north of it even prior to 410–the wall itself represented the boundary of the Roman sphere when it was built in the second century. The entrance of Germans into Britain, moreover, had started well before the Roman departure and had progressed substantially by the later fifth century; it’s generally agreed that the battle of Mount Badon represented a counter-attack by the Britons against them that temporarily stalled their advance, and occurred in the southwest of the island, not in the north at the wall, and that Arthur, if he existed at all, was a Romanized Briton whose “kingship” is a later fabrication. As to the religious side of the story, Pelagius actually flourished in the late fourth and early fifth century, and though he emphasized human free will in man’s struggle for salvation and was eventually expelled from Rome for heresy, he certainly was no exponent of the sort of modern vision of freedom and equality attributed to him here. A bishop named Germanus (not Germanius) of Auxerre, moreover, visited Britain to combat Pelagianism in the 420s and 440s (he died in 448), but while there he’s supposed to have aided the Britons against the Picts and Saxons, he did not represent some fictive Roman control of the area exercised, as suggested here, by the pope. (Rome had, by this time, been sacked by Germanic invaders twice–in 410 and 455–and had been largely abandoned by the emperors. The bishop of Rome filled the resultant power vacuum on the local level to some extent–as when Leo I took a lead in trying to defend the city against the Huns in 451, for instance–but the idea that he had political influence in Gaul and Britain, as the movie implies, is ludicrous.)

Of course, the fact that Franzoni’s script is a tissue of fabrications, tying together bits of vaguely historical material with shards of the later legendary tradition (there are still a round table and a remembrance of the sword pulled from the stone, as well as suggestions that Lancelot might be attracted to Guinevere, too) in a concoction modeled on lots of old movies doesn’t mean “King Arthur” couldn’t be good, dumb fun. Plenty of enjoyable pictures have mangled history in the pursuit of exciting drama. The real problem is that in this case the scenario is played out in such a dull, desultory way that its absurdities are magnified to astronomical proportions. Fuqua’s direction is sluggish and enervated, even in the big, occasionally gory and almost always confusing battle sequences (though they’re a respite from the even more slow, stilted dialogue scenes). Things are certainly not helped by the unremitting visual gloom, with the Irish locations bleached of any lustre by heavy weather and lots of smoke and by the cinematography of Slawomir Idziak, which emphasizes browns and greys. (A few sequences with snow are momentarily attractive, but they’re a distinct exception.) To be sure, the story is set in the period commonly referred to as the Dark Ages, but that’s no reason that the photography has to be so murky. The cast is dreary, too. The stone-faced Owen makes an utterly monochromatic Arthur, and his knights prove a mostly under-characterized group, with Ioan Gruffudd, who was so winning in the A&E series of “Hornblower” movies, especially disappointing as a blandly handsome Lancelot. (The other pallid comrades are Mads Mikkelsen as Tristan, Joel Edgerton as Gawain, Hugh Dancy as Galahad and Ray Stevenson as Dagonet. The only exception to the general colorlessness of the band is Ray Winstone’s loud, boisterous Bors–a name which seems quite appropriate in view of how dull this group of seven, including Arthur, is. And he’s notable primarily because he looks rather like Curly Howard.) Keira Knightly wears her dominatrix-style outfits and “Braveheart”-inspired war paint well enough, but otherwise makes surprisingly little impression, while Stephen Dillane is a stiff, unimpressive Merlin (no magic powers here). The Saxons don’t fare much better. Stellan Skarsgard snarls perfunctorily as Cerdic, the leader of the invaders, but at least his face is largely obscured by a profuse quantity of beard and hair, so he might hope to escape notice. The same can’t be said of poor Til Schweiger, who smolders ineffectually as Cerdic’s son Cynric; the poor fellow is not only forced to sport a comical-looking goatee, but delivers his lines in a grotesque accent that sometimes makes him sound like Elmer Fudd. (For some reason the “Romans”–apart from Arthur, of course–are played by actors who either speak naturally with or affect an Italian accent, which makes no sense whatever.) Meanwhile Hans Zimmer’s score uses all the conventional devices in a failed effort to generate some excitement and awe. On the other hand, if the press notes are to be believed, great attention was bestowed on the details of costume and, especially, weaponry. But one still misses the gleaming swords and glistening armor of a film like John Boorman’s “Excalibur.” It easily remains the most intriguing screen version of the Arthurian legend (transposing it to the Dark Ages too), flawed and bloody (as well as determinedly anachronistic in its details) but imaginative and visually stunning. “King Arthur” could have been a nifty revisionist complement to it, but unhappily it’s hobbled by its cliched script, deadening pacing, unimpressive visuals and wooden performances. As far as big-budget historical epics from Disney go, it’s even worse than the company’s last offering in the genre–the tinny, trite “Alamo.”