It's a rare privilege to be able to go into a movie cold, without foreknowledge of its plot or characters or even its genre, to have no preconceptions or expectations and be able to experience the film purely for what it is. As someone who has to prepare detailed programme notes for film society screenings, and who is thus aware even of the endings of some films before I have seen them, I especially appreciate that opportunity when, once in a blue moon, the chance to sidestep advance information presents itself. The counter-argument would suggest that if you are walking quietly down the road and suddenly get hit hard in the mouth, you couldn't help wondering if you'd have taken the blow better if you'd been just a little prepared for its arrival. But as a title, especially given the film's Eastern origins, Sympathy for Mr. Vengeance comes loaded with suggestion, prompting images of a poster bearing a sweaty young Korean male in a defensive martial arts pose, a look of fiery but determined anger on his face, perhaps even waving a weapon of some sort. Mr. Vengeance takes shit from nobody. Which, as it turns out, is light years from the truth.

I first saw Park Chan-wook's extraordinary fourth feature some time before the Tarantino-led yahooing over his latest, Oldboy. All I'd heard was that this was a remarkable work and the opportunity to see it presented itself and I took it. I didn't know what to expect, and I'm not sure I was quite ready for what I got. I was certainly not prepared for the very disturbing turn the film takes in its last half hour. Those coming to it retrospectively after Oldboy may be better prepared for that, especially if they struggled to make it through that film's notorious dental torture scene.

But then again, maybe not. Sympathy for Mr. Vengeance has none of Oldboy's post-modernist artistic tics or does not share its almost pause-free pacing. Indeed, Park's style here is deceptively low key, all static wide shots, lingering close-ups, and unhurried editing. It also has a storyline that initially borders on the outrageously clichéd, with good hearted deaf-mute Ryu (Song Kang-ho from Park's Joint Security Area) working long hours at the factory to pay for his sister's desperately needed kidney transplant. She can't have one of his kidneys because he has the wrong blood type, and there is no sign of a suitable donor on the horizon. Despite his diligent saving, time is running out, an urgency that further increases when he is laid off from his job. What's a boy to do?

It's here that the film takes its first dramatic narrative twist and turns its back on any hint of melodrama. In desperation, Ryu turns to underground organ transplants as a possible source. It'll cost a lot and he doesn't have the required amount, but the criminals have a solution to this – they'll take one of his kidneys in part-exchange. Ryu is hopelessly trusting and naive when dealing with these shiftiest of people, even helping the gang's aging female matriarch to administer her addiction-led morphine injection. When he wakes a few hours later on a concrete floor, naked and minus a kidney, the gang have fled with both his organ and his money. At this point a legitimate donor becomes available, but now Ryu lacks the funds to pay for the transplant. He needs a lot of money and he needs it fast, and so he and his soon-to-be-girlfriend Yeong-mi (Bae Du-na from Take Care of My Cat) devise a plan to kidnap and ransom the daughter of his wealthy ex-employer Park Dong-jin (the excellent Song Kang-ho from Memories of Murder). What could possibly go wrong with a plan like that?

Park's pace may be sedate but there is a fine economy to his storytelling that requires the audience to pay attention to the small details and to sometimes put the pieces together themselves. Thus, one minute Ryu and Yeong-mi are watching Dong-jin from their car, convinced that the plan is doomed, and in the very next shot they are playing with the abducted child like old relatives on a picnic. Surprisingly, the child happily resides with her adoptive new parents (Ryu's sister knows nothing of the kidnap and believes they are merely looking after the girl for a friend while her mother is in hospital), and starts to look as if things will go their way. But events take unexpected and sometimes tragic turns, twists delivered so effectively that I caught myself holding my head and crying, "Oh God, no!" at the screen more than once on my first viewing. Both Ryu and Dong-jin suffer at the hands of fate, which leads to a final half-hour in which both men become determined to seek revenge on those they believe have so terribly wronged them, and fate eventually pitches them against each other.

Here the film becomes an unflinching examination of the gradual collapse of morality in those who have suffered loss at the hands of others, and the extremes to which ordinary people can be pushed by grief and anger (a theme also at the heart of Oldboy). The emotional complication for the audience is that we sympathise with both men and their respective predicaments, and while we want to see Dong-jin get justice, we don't want Ryu and Yeong-mi to pay the price. In this respect, we are offered the resolution of vengeance that is key to so many western revenge thrillers, but not the cathartic pay-off that this traditionally brings. Sympathy for Mr. Vengeance takes us to far darker places than other such films have dared – it's a revenge story that explores the suffering of those seeking retribution, but also the moral complications and emotional pain that this inevitably leads to.

It is the final act that delivers the film's most horrific sequences. Although much of the violence is off screen or distanced by long shot, the sheer brutality and cold-hearted viciousness with which it is administered is genuinely shocking, especially given the largely sedate handling of the drama that has preceded it. This shift in tone is signposted by a key event early in the story, when recently fired employee Peng stops Dong-jin's car and pleads for his job so that he might support his family, and on failing to convince his ex-employer he opens his shirt and repeatedly slices his own stomach. Startling in itself, the incident later resonates with Dong-jin in a number of ways, notably through the cut he receives to his hand when trying to disarm the man, which twice gives him considerable pause for thought, once when it is mirrored by a second, almost identical injury. Peng's own eventual fate also provides Dong-jin with a tenuous emotional connection to his old life when he seems to have lost everything, and the stomach slashes foreshadow the opening cut of a particularly distressing autopsy that Dong-jin will later attend. This is a scene that has caused considerable debate amongst those I know who have seen the film – many (and this initially included myself) thought it extremely unlikely that any man would be expected or even allowed to view the grisly autopsy of such a close young family member, and believed that its principal purpose – apart from turning the stomachs of the audience with a series of truly horrible sound effects – was to provide a comparison for when Dong-jin unemotionally observes a second autopsy in a later scene. Four viewings in I found myself with a different take on this, and it seems likely that this was a conscious decision on Dong-jin's part to attend and face up to the unimaginable, and that he was able to gain access to this, as he does to the investigation itself, by bribing the appropriate authorities.

The film as a whole is genuinely overpowering, an emotionally gut-wrenching and intellectually thrilling work from one of Korean cinema's fastest rising stars. The overall sense of bleakness should not obscure the fact that there is a fair amount of humour contained within, especially in the earlier scenes, something that becomes more evident on subsequent viewings. In terms of its involvement with the characters, its restrained yet sometimes brutally direct approach and the simple beauty of its construction, it actually outshines the more widely heralded Oldboy. Sympathy for Mr. Vengeance is a superb example of why modern Korean cinema now appears to be leading the pack.

I have to admit that the first time I saw the film on DVD I was convinced that some serious cropping had gone on here, as if the film was shot in widescreen and then vertically cropped in post production to scope. I have had to revise this view after seeing the behind-the-scenes documentary on this disc, which includes shots of the video monitor during shooting which repeatedly shows the picture being framed to 2.35:1 – even the storyboards are drawn in that ratio. But nagging doubts remain about whether this picture has been cropped further for video, as although much of the framing seems fine, a good many shots feel uncomfortably cramped, and there are a fair few in which the tops of heads are awkwardly cut off. Elsewhere, only the lower half of a key poster advertising underground organ transplants is visible (the subtitles provide the whole message), and the first knife cut in the aforementioned autopsy scene starts some way out of the picture area and drifts diagonally into shot in a way that does not feel quite right. At times this seems almost clumsy, and does not sit with the precision of the camera placement at lighting. But I freely admit I have no real evidence to back this up and it may just be a decision on the part of Park and his cinematographer Kim Byeong-il to shoot it this way – after all, the film breaks enough other established conventions. It is interesting to note, however, that Tartan have listed the aspect ratio on the box as 1.77:1, and the framing here is actually 2.21:1, itself slightly unusual. (See my review of the Vengeance Trilogy Edition for more on this.)

The good news is that the anamorphic transfer itself is first rate, with sharpness, detail, contrast and colour – including the slight green dominance Park wanted for some scenes – just right. Blacks are rock solid and the shadow detail is good. There are no distracting compressing artefacts, and although this is an NTSC-to-PAL transfer (the running time and occasional motion blurring are giveaways), it's a damned good one.

There are three Korean soundtracks available: Dolby 2.0 stereo, Dolby Digital 5.1 EX and DTS-ES 6.1. All boast fine clarity and even the humble stereo soundtrack has a decent range and good separation, but does tend to pale in comparison with the 5.1 track, which makes use of the full sound stage and flexes its muscles on the lower frequencies when needed. But even this takes second place to the DTS-ES track, a dynamic mix that is both subtle in its use of environmental and urban atmospherics and thunderous when reproducing factory noise. Separation on both the surround mixes is excellent. Due to the requirements of director's commentary, the audio option can only be changed in the Setup menu.

The English subtitles are generally fine, but are lacking in a couple of key places – notes, documents and computer displays, some of which are clearly important, are left frustratingly untranslated.

The key extra here is the Director's Commentary, although that should be in the plural as Park Chan-wook is joined by fellow director Ryu Seung-wan, whose films include Die Bad [Jukgeona hokeun nabbeugeona] (2000) and No Blood No Tears [Pido nunmuldo eobshi] (2002), and whose brother is actor Ryu Seung-beom, a regular in Park's movies, this one included. This is a very lively and consistently interesting track in which the two men discuss the effectiveness of particular sequences, the process of making the film, the use of music, and even the original intention to structure the film as two stories and shoot one of them in black and white. There is also some interesting info on the numerous cameo appearances in the film, some of which are surprising, to say the least – the four guys seen hanging out in the adjacent apartment and collectively masturbating to what they believe is the sound of sex next door (and is in fact Ryu's sister groaning in pain) are four up-and-coming short film directors. The pair reference a number of western films, some of which, such as the Zucker Brothers' Ruthless People, you would not have seen a specific connection to had they not pointed it out. They also express their admiration for Kitano Takeshi's talent for storytelling through editing. There is also a fair amount of humour here, some of it dryly unintentional – commenting on the scene in which one character digests an internal organ of another, Park says "I thought it wouldn't make people sick. That was a misjudgement." There's not a single dull spot here, and is a very worthy extra. As this is conducted in Korean with subtitles, it cannot be accessed through the audio button, but has to be specifically selected on the Extras menu.

Shot on 4:3 digital video, the Behind the Scenes Documentary (29:57), is a largely formless but always interesting glance at the making of the film, and includes interviews with key cast members and the director, rehearsal and research footage (the cast practicing sign language at a school for the deaf), and some of the technical aspects of the production.

Finally there is the original Korean Theatrical Trailer, which is scope, non anamorphic, and thoughtfully subtitled in English.

The expected Tartan Asia Extreme Trailer Reel has trailers for Oldboy, Battle Royale II, Infernal Affairs, Infernal Affairs II and A Tale of Two Sisters.

What can I say? A great film, a decent transfer, first rate sound, quality extras – only my niggling (and possibly incorrect) doubts about possible picture cropping cause me any problems here. Those coming to the film from Oldboy may find the pace a little too relaxed, but I urge you to stay with it – the film delivers a wallop every bit as powerful as Park's more widely discussed latest, and is an excellent showcase for the talents of this very talented director and his fine cast.