Reviewing on Hollywood Reporter, Todd McCarthy says an urgent desire to take a long shower is an appropriate response to watching The Devil’s Double, so unsavoury is the experience of being immersed in the world of Saddam Hussein’s Caligula-like son Uday and his double, Latif Yahia.

The film was shot in Malta which doubled up for Iraq, Malta being, says Mr McCarthy, “an unexpected effective substitute for Iraq”.

Undeniably fascinating as a visit to a world you’d never have wanted to have come near in real life – that of the Hussein family’s inner sanctum – the film falls crucially short by not providing a window into the mind of the man who was coerced into acting as his double. Dominic Cooper’s riveting double performance and the lurid, beyond-Scarface sensationalism are the main selling points for a film to which it will still be difficult to lure a wide public.

A drunken, drug-fuelled, gun-toting, short-tempered party boy, torturer, rapist and murderer, Uday, with unlimited funds at his disposal and never properly reined in by his disapproving father, would routinely cruise schools in his Porsche or Ferrari, pick up 14-year-old girls, have his way with them and then have their bodies dumped by a roadside. On a whim, he’d drop by a wedding ceremony and demand to defile the bride on the spot. Intensely psychotic, he threw endless bacchanalian parties, revelled in torture videos and avoided anything resembling official responsibilities.

He was widely despised, of course, and, as with his father, it was thought advisable that he have a double to cover for him, throw off potential attackers and so on. In the late 1980s, toward the end of Iraq’s long war with Iran, it was the misfortune of army lieutenant Latif Yahia to be handpicked to fill the job, the full dimensions of which would have been hard to foresee.

With the fate of his family held over him if he declines, Latif undergoes plastic surgery and dental work to enhance the resemblance, learns to match Uday’s higher-pitched voice and vocal patterns, acquires a double of his wardrobe and is installed in a life of luxury, including a selection of women, while always being on call if needed. Mostly, he’s just another member of Uday’s sinister entourage, passed off humorously as Saddam’s “third son” (curiously little is seen of the dictator’s actual other son, Qusay).

Guided through his paces by a wise old mentor, Munem (Raad Rawi), Latif clearly disapproves of Uday and his sleazy lifestyle, but there’s nothing he can do except sullenly go along. Unfortunately, director Lee Tamahori and screenwriter Michael Thomas (The Hunger, Scandal) aren’t able to make Latif the viewer’s confidant, to effect a viewer’s personal connection to his strange odyssey; instead, one is simply left a spectator at a Roman circus.

One way to supply this would have been a Latif voice-over, perhaps in the style of Ray Liotta’s in GoodFellas. Another would have been a deeper, more revealing liaison between Latif and Sarrab (Ludivine Sagnier), Uday’s main squeeze, who dares to launch a relationship with his double. Given that there can be no secrets in this world, how this affair is allowed to continue is never explained, but a more intimate connection between the two might have provided the lacking human dimension.

When the US steps in to aid Kuwait, Uday rails against the enemy but sends Latif to the front to rally the troops instead of going himself. Outrage follows outrage until, finally, Latif manages an escape, leading to a dramatic climax that ends the film well before Uday’s death during the American invasion years later.

Tamahori makes sure there’s never a dull moment, although the succession of mindless disco parties, coke snorting, assaults on helpless women, psychotic rants and unmotivated violence has a cumulative deadening and depressing effect that is never leavened by an artistic vision or historical take on the grim spectacle. Although energetic and visually and aurally dynamic, this feels like a job of work rather than something more ambitious and felt from the inside.

With shooting in Iraq impossible, the filmmakers found an unexpectedly effective substitute in Malta. Having just worked on Green Zone, production designer Paul Kirby has done a terrific job creating both the grand exteriors and ornately vulgar interiors of the Hussein regime, an effect elaborated by Anna Sheppard’s costume designs and Sam McCurdy’s cinematography. Christian Henson’s score and various source music choices are effective at generating a dark, turbulent mood.

In utter command of both roles, Cooper differentiates between the two beautifully, suggesting Latif’s necessarily restrained natural cockiness and seething resentment at his lot in life while letting out all the stops as the mercurial Uday. He’s really the whole show, although it’s too bad the script restrained him from further illuminating Latif’s inner self.

The film doesn’t mention that, in real life, Uday and Latif had been schoolmates and that their close resemblance had been noted since youth. Furthermore, the third act particulars of Latif’s escape and subsequent events seem to have been fabricated out of whole cloth. Latif’s autobiography was published in 1997 but only became an international best seller after 9/11.