Dir. Kong Su-chang. South Korea . 2008. 122 mins.

Like Park Chan-wook's Joint Security Area (2000), The Guard Post is set on the edge of the demilitarized zone that separates the two Koreas. Also like JSA, it uses an investigation into an incident involving a group of army recruits as an excuse to probe a geopolitical divide which is also a national trauma. But whereas JSA was a serious drama, The Guard Post is framed as an often gruesome horror-thriller with zombie overtones.

This not a standard Asian horror product, however- more of a thriller with gruesome detailing. High on tense and claustrophobic atmosphere but low on character development and dramatic coherence, it still has enough attitude to appeal to fans of the director's strikingly similar 2004 'military horror' R-Point, and niche DVD labels may want to take a look. In Korea, The Guard Post debuted in first place on its 3 April release, but has since tailed off: final takings are likely to be respectable but hardly overwhelming.

The picture starts compellingly: Guard Post 506 has not phoned in to HQ - as these border forts are required to do every half hour - so military police led by sergeant major Noh (Cheon Ho-jin) are sent in to investigate. They discover a scene of carnage, with crazed, axe-wielding Private Kang (Lee Byung-hun) apparently the last man standing - and thus the obvious suspect. The investigation is complicated by the fact that the post is commanded by a prominent general's son, Lieutenant Yu (Jo Hyeon-jae), who soon turns up, terrified but alive.

Before long we're cutting back and forth between now and pre-massacre as Noh begins to uncover clues in diaries and reports. But with both the present MPs and the past troops in identical military fatigues and no stylistic signals to help us, it's often difficult to work out what time frame we're in. Towards the end it becomes clear that this is deliberate; but it's a long and confusing wade, and we're given only the most cursory character sketches.

A sortie into the demilitarized zone introduces a virus into the camp, and gradually The Guard Post veers from investigative policier to quasi-zombie flick - though it stops just short of tipping over into parody.

Too long at just over two hours, The Guard Post never really quite hangs together, but a decent genre film keeps peeping though the mess

The last twenty minutes finally lend the proceedings a certain dramatic logic and coherence, and there's no denying Kong's feel for atmosphere. If only the tired script were of the same quality.

Production companies

Showbox Mediaplex

Bokko Pictures Inc

International sales/world distribution

Showbox Mediaplex

+82 2 3218 563

Producers

Kong Su-chang

Im Jeong-hwa

Kim Wan-shik

Screenplay

Kong Su-chang

Pil Young-woo

Cinematography

Kim Seong-hwan

Production design

Jang Chun-seop

Editor

Shin Min-kyung

Music

Choi Seung-hyun

Main cast

Cheon Ho-jin

Jo Hyun-jae

Lee Byung-hun