A hit-and-run lands a cop in more trouble than he could ever have imagined in "A Hard Day," a South Korean police thriller that finds helmer-scribe Kim Seong-hung handling a taut yet elaborately plotted narrative with poise, control and near-faultless technical execution. Though punctuated with skull-cracking combat scenes and propulsive chases, the pic doesn't indulge in the stomach-churning gore that saturates so many Korean actioners; in fact, it's the nerve-racking situation that faces our hard-luck protag, with its heady black humor, social satire and a touch of surrealism, that keeps audiences on the edge of their seats. This slick genre vehicle should drive smoothly into most Asian-friendly territories, especially in ancillary.

Right in the middle of his mother's funeral, homicide detective Ko Gun-soo (Lee Sun-kyun) is called out by his team members to hurry back to the station, as the rat squad (internal affairs) is raiding their office. While speeding down the pitch-black highway, he swerves to avoid hitting a beagle and ends up running over a man. Braving the most conscience-pricking stare from his pooch witness, he hastily stashes the body in his trunk and keeps going. His attempt to make it through a roadblock guarded by officious traffic wardens is just the first of many nick-of-time scrapes that will hold audiences in suspense.

Things come to a head at the funeral parlor, when his chief (Shin Jung-keun), together with his teammates, try to make him take the heat for their collective racketeering (the rat squad busted open Ko's drawer to find stashes of bribe money). In a morbid example of necessity being the mother of invention, Ko hits upon a novel way of disposing of the body (albeit one that puts his mom in a tight spot), in an extraordinary stunt sequence that melds Hitchcockian tension and Keatonesque slapstick.

The more Ko tries to cover his tracks, the deeper he's digging his own grave. After a sudden order from above to reopen cold cases, he learns that the man he ran over was a small-time crook with connections to an underground vault service. Enter a stalker who claims knowledge of Ko's crime, and before long, our hero is in the clutches of Park Chang-min (Cho Jin-woong) a nemesis so potent and diabolical that he leads the film to a gripping turning point.

There's really nothing groundbreaking about this Faustian relationship, but it plays cleverly with audience loyalties. Ko's resourcefulness and almost bloody-minded resistance to intimidation or control make one root for him, despite his professional conduct, and lack of moral fiber. Lee, who turns up regularly in Hong Sang-soo's works as well as starring in a huge range of commercial films, brings just the right amount of intensity to his performance, and impressively generates laughs without ever playing the fool or clown. Likewise, Park proves a formidable opponent, and Cho makes the most of his chubby face to project a personable air that belies his utter ruthlessness.

In line with recent hits like"The Attorney," which reflect national discontent over the rise of political cronyism and social inequality, the film is rife with acerbic depictions of the police's casual criminality. The characters' sense of entitlement, whether bullying juniors or bending their rules to their liking, hints at a system that's rotten to the core, and it's capped by an amoral final twist that brought down the house at the film's Directors' Fortnight premiere.

Where the film appears inadequate is in its shallow portrayal of Ko's relationship with his family and colleagues, as well as in its lack of psychological penetration; there's not a single moment when he shows remorse at having killed someone, albeit by accident.

Choi Dong-hun's action direction eschews fancy effects for bone-crunching realism, most notably during a tussle in a toilet that gets effectively nasty. The mano-a-manos between Ko and Park are set in ordinary locations but play out with animalistic ferocity, like dogs fighting over a bone. In true spirit of Korean noirs, no character shows any mercy. Kim Tae-sung's lensing shifts dramatically between oppressively tight closeups of combat and breathtaking high-angle and flyover shots of chases and driving sequences, expressing the protag's agitated state of mind.

Editor Kim Chang-ju's precise, gimmick-free pacing enables the plot twists and shifts in character behavior to feel natural and credible. Mok Young-jin's haunting score closely mirrors the protags' moods, while the Dolby 7.1 surround sound makes its impact felt not through nonstop head-banging effects, but via eerie moments of calm before the storm.

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