Based on Jon Ronson's eye-opening true tale of unhinged US military experiments, this adaptation shoehorns a hackneyed Hollywood story structure into the craziness and doesn't quite make its point... but it's just too enjoyable to ignore.

Small town journalist Bob Wilton (McGregor) is going nowhere fast when a chance interview with a local oddball brings a shocking secret to his attention.

It seems that the US military has been carrying out research into psychic phenomena with the intention of harnessing supernatural abilities on the battlefield.

Dumped by his girlfriend, Wilton has nothing to lose as he heads to Iraq to find Lyn Cassady (Clooney), a so-called 'Jedi warrior' in America's psychic army.

While initially suspicious, Cassady is soon spilling the beans on the remarkable unit, the time he killed a goat with the power of his mind, and the guru behind all the insanity, Bill Django (Bridges).

As the two head across the Iraqi desert in search of Django, Wilton faces kidnapping, land mines and Lyn's apparent loopyness as he struggles to get to grips with the mind-boggling story.

With the main players effortlessly slipping into familiar roles, The Men Who Stare at Goats is a subversive treat with a twinkle in its eye.

Clooney's military mentalist is an endearing blend of Archie Gates from Three Kings and one of his Coen Brothers goofballs; the moment where he earnestly informs Obi-Wan Kenobi actor McGregor of his Jedi credentials being worth the price of a ticket alone.

Bridges is similarly spot-on as the new age mastermind, dusting off his laid back Big Lebowski persona to deliver another crowd-pleasing pothead in some memorably barmy flashback sequences.

As Black Hawk Down proved, Ewan McGregor really should give American accents a miss. But, dodgy dialect aside, he brings a puppy dog enthusiasm to Wilton that is crucial to the film's frothy energy and outlandish laughs.

It's the ham-fisted attempt to weld fictional elements onto Ronson's amazing true story that causes problems.

Tying the writer's alarming discoveries into a neat narrative bundle not only feels artificial, but it also blurs the lines between truth and artistic exaggeration, the startling nature of the facts becoming tarnished by silly fiction.

A disappointingly generic finale gives way to an ingenious final gag, however, with the gleefully anarchic spirit that drives the film leaving a much bigger impression than the patchy story.

Chris Prince