If I've learned one thing from recent Korean cinema it's this: if you are visiting the country – and I have an open invitation to do so in the near future from a Korean friend of mine – then don't get arrested for anything. If by some misfortune you do and are approached by two detectives, one slim, one a little more portly, then whatever you do don't let them get you in a room alone with them. If movies are to be believed, by the time you re-emerge, you'll have admitted to anything they have choosen to accuse you of.

Large detectives with slim partners who abuse those in their charge are becoming a regular feature of modern Korean police dramas – even the seemingly civilised pair who visit the floating monastery in Kim Ki-duk's Spring, Summer, Autumn, Winter... and Spring seem to have this size/weight distribution thing going. A similar pair are at the centre of Bong Joon-ho's Memories of Murder, and although this is one of several familiar elements to be found in the film, it avoids both the heavy borrowings from western cinema found in Public Enemy and the overboard post-modernist visual trickery of Nowhere to Hide, putting a fresh spin on every one of them and integrating them seamlessly into a compelling and vividly realised whole.

The majority of police dramas seem to be set in the bustle of the city, where violent crime is more commonplace, where investigations can be frustrated by bureaucracy and non-co-operation, where criminals can be lost on subways and down alleyways, and where cars can chase each other through traffic and red lights at pulse-raising speed. Based as it is on the true case of Korea's first recorded serial killings, Memories of Murder takes place instead in a rural district in the Gyeonggi province back in 1986, when the country was still under military dictatorship.

It all kicks off when the body of a young girl, tied-up and abused, is found in a farmland drainage ditch. Local detective Park Du-man (Song Kang-ho) arrives to investigate, and is frustrated to find the crime scene compromised and out of his control, a situation that also plagues the discovery of a second body a short while later. Into this world walks introspective, thoughtful, Seoul-based city detective Seo Tae-yun (Kim Sang-kyung), who has taken an interest in the case and whose more studious working methods are initially scorned by Park and his partner Cho Yong-ku (Kim Roe-ha), but which soon turn up some useful and unexpected leads.

One of the many elements given a makeover here is the old story of a boy from the city bringing his working methods to country folk and meeting local resistance, which right from the start doesn't play as expected. Rather than trying to take charge, Seo requests a desk in the corner of the station house and silently observes his two new colleagues going about their business in their uniquely clumsy way. Park and Jo have their own particular version of the Good Cop/Bad Cop routine, in which Park coerces information from a suspect through a mixture of subtle intimidation, misdirection and faked evidence, and Jo simply kicks the living shit out of them. His assaults leave no tell-tale scuff marks on the suspect because before administering a beating he covers his shoe with a garment of patterned design that looks as if it was made for him by his mother. As a method of extracting confessions it is largely effective, but as a way of getting to the truth it is hopeless, as a week spent in the boiler room with these two would prompt you to admit to just about anything to get them to leave you alone. That Seo quietly despairs at this approach does not surprise – what does is that he does not try to correct Park's behaviour, but instead all but ignores him and his partner and carries out his own enquiries behind their backs. This split methodology is especially evident in the early stages, where the film focuses primarily on Park and Jo, whose own dead-end investigations are suddenly usurped when Seo pipes up and presents crucial evidence to the Chief that leads directly to the discovery of another body.

It's somewhat inevitable that Park and Seo will eventually learn to work together, but the journey to that moment is rich in sometimes glorious character detail and full of unexpected narrative side-steps, though the storytelling never loses focus for a second, with even the smallest incidents in some way driving the plot forward. Character convention tells us that Jo will have to step aside in order for Park and Seo to work more closely with each other, but that Jo is eventually suspended for doing exactly what he has always done is a little ironic, while the moment when Park looks mournfully at the patterned shoe-cover with which his partner used to pummel his victims is without doubt the most perversely poignant in the film. Both Park and Seo are transformed by the case as they feed off of each other's personality traits – Park, it turns out, really does want to solve the mystery rather than just bang someone up for it, whereas Seo's frustration at the perceived failing of his own coda, "documents do not lie," eventually vents itself in physical violence.

Serial killer stories have their particular and peculiar fascination, and Memories of Murder is no exception, but it stands apart from so many of its sub-genre companions by focussing exclusively on the police investigation and by telling its story with such tightly structured efficiency, with all of the necessary twists and surprises delivered with the precision timing of a perfectly engineered Swiss watch. Director Bong Joon-ho builds on this by suddenly shifting tone at unexpected moments, a technique that ensures you are never quite sure where the film will take you next. Thus, character-driven prolice procedural scenes can suddenly give way to moments of comic hilarity (a brief sequence in which Park, convinced the killer has no pubic hair, spends a day in a bath house eyeing up the bathers' genitalia is a hoot) or palpable terror (a potential victim is terrorised by sounds in field at night and runs for her life, only to have the killer leap up in front of her). Nowhere is this better demonstrated than in a night-time stakeout of a murder scene, where tense apprehension suddenly switches to perverse comedy, then to a breathless on-foot chase in which all three detectives pursue who thy think is the killer, but who turns out to be a frustrated family man who was getting off by having a quiet wank at the crime scene.

In some respects, the film has the key hallmarks of a work by Japanese maestro Kitano Takeshi, in the compression of information through economic editing, the deliberate pacing of scenes, the oddball character detail, and an initially Joe Hisaishi-like score from Japanese composer Irashiwo Tarah. As a whole, though, despite being a very different film, it shares some surprising common ground with Curtis Hanson's L.A. Confidential, in its sudden and unexpected shifts in tone, in the timing of its narrative surprises, in the events that initially divide but ultimately unite the two seemingly irreconcilable lead characters, and particularly in the sheer quality of its storytelling and the assurance of its filmmaking. Where the two really part company is in the later stages, with Bong staying true to the case on which the film is based, something there would likely be studio pressure to change in a Hollywood take on the story.

The performances of the entire cast, from the leads to the bit parts, are bang on. Song Kang-ho, who was so good in Park Chan-wook's Sympathy for Mr. Vengeance [Boksuneon naui geot], really shines as Park, his comic timing and sheer physicality (his first encounter with Seo, whom he mistakes for a potential rapist, sees him land a two-legged drop kick square in the centre of the man's chest) really working for a character who is engagingly likeable, occasionally very funny, but sometimes frustrating in his loutish refusal to accept the opinions or work of others. This is particularly evident in his treatment of policewoman Kwon Kwi-ok (Ko Seo-hie), whose key discovery regarding a radio broadcast he laughingly dismisses, then handing her his teacup in a gesture that almost casts her as the office domestic. Seo, on the other hand, not only takes her seriously but makes good use of her talents, asking her to conduct a key interview with a distressed female witness he knows will likely only open up to another woman. You can't help but feel that if Kwon returned to Seoul with Seo, she would very quickly become a detective of some standing herself. As the quiet and reclusive Seo, Kim Sang-kyung does not really get to show his worth until the later stages, where his emotions finally boil to the surface and he has to confront the failings of the very system in which he has invested so much faith. In the final scenes, his anger and pain register all too clearly, but he never lets this slip into melodrama – it's a largely unshowy but very nicely judged turn that perfectly counterbalances Song's more brashly comical Park.

To integrate comedy into a thriller based on such a notorious real case and make it work without ever diminishing the seriousness of the crimes is no small task, but to do so with the deftness Bong displays here is little short of miraculous. This is partly achieved by ensuring that even when there is an absurdist element to the narrative – Park and Jo taking a break from beating up on a suspect to enjoy a meal and a favourite TV show with him, for instance – it never feels preposterous, just a little eccentric, and it always works for the character and story. A great example of this occurs early on, when a superbly organised and executed steadicam shot follows Park's arrival at the second crime scene, as members of the forensic team fall arse-over-tit down a grassy bank and a farmer ignores Park's shouts and drives his tractor clean through a vital footprint, a sequence that is not staged purely for laughs but to economically outline the inexperience and incompetence of the local police force when it comes to handling a crime of this nature. That Bong interweaves the drama with scenes that reflect a time of political repression and change for the country is interesting in itself, but once again he makes this crucial to the story, notably when efforts to catch the killer are frustrated because the required manpower has been diverted to suppress a demonstration elsewhere.

Memories of Murder is filled to the brim with such detail, but it is far more than just a collection of great scenes and engaging characters. It succeeds most of all because, like the aforementioned L.A. Confidential, the parts are all melded into a tremendously well rounded, involving and entertaining whole. Wonderfully performed and beautifully photographed by Kim Hyeong-gyu, Memories of Murder is directed with a confidence and style that must mark relative newcomer Bong as a filmmaker with a serious future ahead of him.

Framed at 1.85:1 and anamorphically enhanced, the transfer here is gorgeous, a pin-sharp picture that reproduces the film's subtle use of sepia tinting very nicely indeed. Colour, within the restrictions imposed by the film itself, is bang on, black levels are excellent, and contrast, though a tad strong, is generally fine. No obvious signs of edge enhancement were present – and I was looking for them after seeing how sharp the picture was – and artefacting is kept to an absolute minimum.

With the upcoming region 2 release promising only a Dolby 2.0 soundtrack, the 5.1 and DTS tracks here give this disc the technical high ground, and both really work for the film. The separation is excellent right across the soundstage, with very effective use of the rear speakers – music often washes over the whole room, though surprisingly little use is made of the lower frequencies. Of the two tracks, the DTS is noticeably richer, and has more definition.

In terms of extras, this Hong Kong release lags behind both the Korean 2-disc set from CJ Entertainment and the upcoming region 2 release from Optimum, though it should be noted that the extra features on the Korean release lack English subtitles.

First up with have the Theatrical Trailer, with is presented 1.85:1 non-anamorphic and, unusually for a trailer, has both Chinese and English subtitles.

Behind the Scenes is 11 minutes of DV footage watching the actors at work on various scenes, and is made up almost exclusively of out-takes. The entire cast seem ready to burst out laughing at the slightest provocation and the atmosphere on set comes across as very relaxed, the relationships between the cast and crew cheerfully positive. This is great fun to watch, even without the aid of subtitles (you don't really need them), and made me wish for more of the same.

There are 3 brief TV Spots, none of which have subtitles, but at 11 seconds each they don't really need them.

Photo Gallery has 13 production stills, all about half screen size.

Filmographies has, well, brief filmographies of the two lead actors and the director, in both Chinese and English.

Memories of Murder was one of the best films released in the UK in 2004, a gripping, intelligent and occasionally hilarious character-driven crime drama, far more low key than most recent Korean police thrillers and most Hollywood takes on the serial killer sub-genre. It also rewards repeated viewing and is definitely a film that anyone with even a passing interest in this subgenre should own. I, for one, can't wait to see what director Bong Joon-ho does next.

UK viewers may want to hang on for the upcoming region 2 release from Optimum, which has some interesting-looking extras, but if the reports of a Dolby 2.0 soundtrack are true then I'd be tempted to go either for this disk (which can be picked up on-line for about £8) or the Korean 2-disk edition and rent the Optimum disk to check out the extras – after all, how many times are you going to want to view them, whereas the film is one I have already come back to three times, and the picture and sound here are terrific. It has to be said that the comedy elements worked best in the cinema with a large audience, but the sheer skill of the storytelling, the richness of the characterisations and the skilled technical handling make it seem fresh every time I see it. If you've seen it already then it's just a matter of which disk to go for – if you haven't, then I'd move to to the top of your Must-See list immediately. You won't regret it.