Award-winning screenwriter Scott Frank, who penned Minority Report, Get Shorty and the smouldering George Clooney-Jennifer Lopez thriller Out Of Sight, makes a seamless transition to director with his own ingenious creation.

The Lookout takes that most reliable and well-oiled plot device, the bank heist, and envisages it from the perspective of the most unlikely and ill-equipped robber imaginable: a young man crippled by brain damage.

It's a daring ploy that could so easily be dismissed as a cheap gimmick, but Frank writes with flair and sensitivity, sketching the characters with great affection.

A tour de force central performance from Joseph Gordon-Levitt further distinguishes the film.

He eschews a flashy, mannered interpretation of an addled mind in favour of stillness with occasional flashes of rage and despair as his emotionally battered loner seeks to make sense of an alien world.

Brilliant high school hockey player Chris Pratt (Joseph Gordon-Levitt) is involved in a terrible car accident and suffers devastating brain damage.

Plagued by short-term memory loss, a lack of inhibition and basic organisational skills, Chris is dependent on his roommate and mentor, a wisecracking blind man called Lewis (Jeff Daniels).

After a long night working as a janitor in the Noel State Bank & Trust, Chris retires for a drink at a bar where he runs into charismatic old school acquaintance Gary (Matthew Goode).

He sympathises with Chris and proposes a daring solution: to help him and accomplice Bone (Greg Dunham) rob the bank.

All Chris has to do is keep an eye out for local cop, Ted (Sergio Di Zio), who often drops by with a box of doughnuts.

In return, Gary promises to hook Chris up with sexy stripper Luvlee Lemons (Isla Fisher). Can Chris resist?

Most heist thrillers rely on an audacious final reel twist to set themselves apart.

The Lookout, by design, cannot entertain such narrative sleights of hand.

Chris is not stupid but with his leaky memory and shattered confidence, he is lost without Lewis and his trusty notepad to lead him through some of life's simplest tasks.

Gary and his shady associates exploit these weaknesses, but writer-director Frank also turns them to Chris's advantage without sacrificing plausibility.

Gordon-Levitt is mesmerising as the hero haunted by misdeeds of the past, and he shares great rapport with Daniels's deadpan best friend.

Goode, Fisher, Dunham and Di Zio offer strong support and Frank directs with assurance including a stunning car crash sequence and a denouement that leaves you with a wry, contented smile on your face.