RIDLEY SCOTT’S crusade to Jerusalem is a thumping medieval yarn, dressed in all the bloody trappings that made his last box-office epic, Gladiator, such a terrific watch. Kingdom of Heaven is a Boy’s Own version of the 1187 battle to save the Holy City from Saladin, and it’s as bitter and lopsided as one could wish. The Christian knights are mouldy cynics. The Saracens are polished snakes. The twists are marvellous. And dying with an axe in your head is a fine art.

But there is controversy in the stalls. Scott has reawakened an ancient fixture between Muslims and Christians, and prominent academics are reacting like boozy football fans. First up for the Millwall Templars is Professor Jonathan Riley-Smith, who declares that the film is not historically accurate. It depicts Muslims as sophisticated, and the crusaders as brutes and barbarians. Khaled Abu el-Fadl, a professor at the University of California, puts in the boot for the Fulham Fundamentalists: “I believe this movie teaches people to hate Muslims. How are people going to react to these images of Muslims attacking churches and tearing down the Cross?” he froths.

This kind of venom should hardly be a surprise for Ridley Scott. Every big film he makes begs to be taken to task. But claims of hatred and bias are feeble. Scott has always been a “shoot first, think (much) later” director, and I admire him for it. He immerses you in the period and action, and leaves you to extract the political shrapnel. What’s strange about his latest film is that it’s so old-fashioned. The hero of the hour is Orlando Bloom, and he bursts on-screen like a hand-crafted aristocrat from the pages of a vintage Mills & Boon. He wears blowsy shirts, dusty britches and medieval cowboy boots when he’s impressing the natives, and chain-mail armour and a huge glistening broadsword when he’s chopping them in half.

He is fabulously uncomplicated, and effortlessly sexy. He’s also grown up from juvenile swashbuckler to handsome and earthy lead. At the start of the film he is a village blacksmith with impeccable aristocratic credentials, a trim beard, a ghastly past and a yen to go to Jerusalem to atone for his murderous sins. But the road to salvation is treacherous. The motley band of knights he is forced to join are as spiritually bankrupt as their Christian cause.

Jerusalem is the usual thousand-year tease: it’s a state of mind, a rape date and a ramshackle casino. The decent chaps who run it are fast going out of fashion. But being a lord, and honourable hero, Balian of Ibelin (Bloom) has an honesty that bewitches the king, and a charm that bedevils the enemy. In short he believes in the crusading faith, yet he retches at what the crusaders have become.

Bloom’s shining idealism is a beacon in a city teeming with crooked barons and back-stabbing plots. David Thewlis, Marton Csokas and Jeremy Irons put in superb cameos as seasoned cynics.

And Bloom himself is torn between his loyalty to God, a married princess (Eva Green), and the leprous king (Edward Norton).

But the film really lifts off only when Scott unleashes the dogs of war. He has never shied away from hardcore combat. Whether we care to admit it or not, a lot of screen pleasure in any Scott epic is invested in the pure claustrophobic horror of his set pieces. He puts the viewer in the eye of the storm. He rams horses into each other at full speed. He creates a bloody maelstrom with no exits to speak of, and he frames every grisly thump at head height or waist level.

Defending the hallowed city against the tidal wave of Saracens — who march and grunt like hungry orcs — is, of course, meat and drink for Bloom. His canny and preposterous arts of survival will raise a sceptical eyebrow. But this is what star and director do best: crazy odds, and bone-crunching visceral violence shot with tremendous flair and style.

“Convert to Islam. Repent later!” shrieks a cowardly bishop when giant pots of flaming oil are flung over the ramparts by Jurassic-looking Saracen trebuchets. It’s a small but priceless piece of comedy.

Bloom rallies his motley force of green-eared boys, plucky depressives and local plumbers like Henry V before the Battle of Agincourt.

The last act is stirring if predictable mayhem, full of eye-watering speeches designed to bring a tear to the eye and a lump to the throat. The Muslims, led by Ghassan Massoud’s upstanding Saladin, have the manners to wait, and the grace to forgive. In fact they come out of this film as the squeaking heroes. But try smuggling that notion past the Academy without having your plimsolls X-rayed.

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