There are certain things that immediately inform an audience that they are watching a European film rather than a mainstream American one. Obvious indicators such as language and location aside, European films frequently use actors who resemble real people rather than the groomed mannequins of the typical Hollywood product. In Hollywood, the same old operators are still too often in place – good guys are attractive, bad guys are ugly, anyone with a beard is probably untrustworthy, and young is almost always better than old. The argument goes that American movies provide the audience with characters that they aspire to be, whereas a European film reflects how things really are. This also extends to a large degree to television. You want a prime example of this? Compare two successful soaps, Dallas and Eastenders. In Dallas it was not just looks that the audience was invited to desire, it was property and wealth and social standing. Say what you like about Eastenders (and I do), but the cast look exactly like the people whose lives they are dramatising, and the problems they deal with are ones we recognise as real.

You'll find no better example of this casting diversity right now than Head-On's lead actor Birol Ünel. He has a great face – rough, weather-beaten, pock-marked and scarred, but somehow still ruggedly good looking, though not in the Hollywood design-a-visage way. Despite his considerable talent as a performer, he doesn't look like an actor – he looks exactly like what he is, a man beaten down by life and by drink.* If Hollywood were to (God forbid) remake Head-On, I shudder to thing who'd be cast in the lead. They'd ruffle his hair and give him a two-day beard growth but he'd still be Tom Cruise or Mel Gibson or whoever might be in vogue at the time, and Cahit's later facial transformation, here so believable, would just turn designer scruff Cruise back into smiley teeth Cruise. Remember Keifer Sutherland at the end of episode one of the second series of 24? I nearly kicked the TV across the room. And I have a big TV.

Anyway, back to this movie and a little bit of plot. Cahit is a German citizen of Turkish birth and caught in a spiral of nihilistic, alcohol fuelled self-destruction. One night, after being thrown out of a bar for assaulting another customer, he drives headlong into a brick wall in what appears to be a deliberate but botched suicide attempt. At the hospital he is approached by the younger Sibel, who has also tried to kill herself, in her case a reaction to the oppressive and sometimes aggressive actions of her traditionalist Turkish family, who strongly disapprove of her active social life. She presents Cahit with a proposal, a marriage of convenience that would allow her to enjoy her liberal lisfestyle away from the ever-watchful eyes of her family. Initially hostile to the idea, Cahit reluctantly agrees, but the two have not been together long when Cahit finds himself attracted to his new room-mate.

Cultural elements aside, you'd be forgiven for a smile of recognition on reading the above. In movies at least, men and women, no matter how different and seemingly mismatched, always seem to get together sooner or later, and the moment Cahit agrees to the marriage it seems inevitable that his relationship with Sibel will develop beyond the purely practical. Director Fatih Akin, himself a German Turk, knows this and perhaps even relies on our recognition of this familiar odd couple set-up – Cahit is some years older than Sibel and a slob two steps away from vagrancy, while she is youthful and strikingly attractive – as after an hour of leading us down a familiar but still problematic path, he throws an almighty curve ball that turns the narrative completely on its head. We are just over halfway in and all the familiar generic assurances are effectively thrown out of the window.

If the set-up sounds familiar then Akin makes it seem fresh, not least because although this is at heart a story of two people drawn to each other against the odds and tested by adversity, it is also a film about cultural dislocation and value rejection. Cahit is Turkish by birth but sees himself now as German, expressing dislike for the traditions of his people and his newly adoptive family. "I hate all this Turkish crap," he complains to Sibel as he is driven to a family get-together, at which he infuriates the young males by suggesting they fuck their wives instead of visiting the brothel (what angers them is his use of the word 'fuck' in relation to their spouses). He is bemused by the wedding rituals and is no longer able to speak the Turkish language with any level of competence. Sibel, likewise, rejects the traditions that her family still hold dear, which she believes are suffocating her enjoyment of life. "Do you think my nose is nice?" she asks Cahit. "My brother broke it because he caught me holding hands." Married to Cahit and freed from her family's grip, she embraces promiscuity with a gleeful vengeance, even copping off with a barman on her wedding night after being thrown out of their apartment by Cahit for asking about his late wife. It is here that we begin to understand just why Cahit is so self-destructive, the pain he is nursing, what he lost that also robbed him of the fire of life.

As the two patch things up, Cahit lands Sibel a job with hairdresser Maren, his on-off girlfriend and another of the film's great faces. Here a clear distinction is made between love and sex, defined by what Cahit desires of Sibel and what he gets from Maren. His sex with Maren is energetic and passionate and presented with a frankness that distances the film further from its Hollywood brethren, and yet it never feel gratuitous, included as it is to clearly communicate the purely physical nature of their involvement. When Maren chooses to reveal their relationship to Sibel, she says simply, "Cahit and I fuck sometimes."

It is no surprise when Sibel's enthusiastic embracement of life not only begins to rub off on Cahit but acts as a candle for the love that he keeps aggressively buried. In the film's most electrifyingly vibrant sequence – as Cahit and Sibel bop and enthusiastically converse to the strains of The Temple of Love by The Sisters of Mercy, climaxing with the decision to go clubbing and Cahit's explosive proclamation that "Punk is not dead!" – the connection between the two is keenly felt, but is immediately undermined with a mid-song cut to Cahit's club of choice, where he is left looking mournfully on from the sidelines while Sibel nails that evening's companion. Even when Sibel does start to feel for Cahit there are complications, but initially recognition alone is enough for Cahit, who slams his hands down on two beer glasses with the loud proclamation "I'm in love!" and leaps on stage and dances with the club band, hypnotised by his awakening, blood pouring from his injuries. Now this is the power of love.

If Sibel's initial attempt to clean Cahit up (she transforms the Withnail/Marwood-like disarray of his apartment and tries to tidy his straggled hair) is on traditional ground, the partial personality exchange that occurs later is not. As Cahit temporarily drops out of the story, Sibel relocates to Istanbul and reconfigures her identity, which has effectively been wiped by her father's sense of shame. Back on Turkish soil she is forced to subjugate her previous lifestyle and conform again to the expectations of family after being taken in by her sister, who is herself undergoing a cultural mutation, eagerly embracing the greed of Western capitalism, her apartment dominated by a large widescreen TV that constantly plays the English Eurosport channel.

In the film's toughest sequence, Sibel hits rock-bottom in every respect and is physically and morally transformed into the Cahit we meet at the start of the film, a nihilistic, drugged up and self-destructive figure who is seemingly begging for a punishment that will serve as some sort of attrition. The transformation is linked to the music score, with the rock tracks that follow Cahit in the first half and help shape his identity disappearing with him from the story in the second, only re-emerging briefly to accompany the wasted Sibel as she dances drunkenly in the bar in which she now works, the flattering clothing of her wild days in Germany replaced by what almost looks like Cahit's cast-offs.

By the final act, both Cahit and Sibel have undergone life-changing experiences, and it is to Akin's real credit that he leaves it to us to join the dots and realise just what has transpired. Both rediscover a  sense of cultural identity, but on very different terms and which may or may not include each other. The film ends as it began, on a group of traditional Turkish musicians who, seated against the backdrop of Istanbul, have functioned as both a Greek (well, Turkish) chorus and the narrative chapter stops, reminding us in the first half that despite its setting, this is essentially a Turkish story rather than a German one.

As a drama, Head-On is bold, exciting, compelling and occasionally brutal; as a love story it is honest, unsentimental and even heartbreaking; and as a study of people caught in a cultural wasteland its is intelligent and heartfelt. The performances, notably Birol Ünel as Cahit, Sibel Kekilli as Sibel and Catrin Striebeck as Maren, are consistently excellent, and the storytelling and filmmaking are both first rate. If its power is fractionally decreased on the smaller screen then it matters not – Head On is still one of the finest films to hit UK cinemas and DVD players this year.

Framed at 1.85:1 and anamorphically enhanced, the transfer provided by independent distributors Soda Pictures is very good, coping equally well with scenes set in bright sunlight and half-lit night. Detail and contrast are impressive, with solid black levels and only minimal evidence of grain. The film's sometimes warmly tinted colour palette is effectively reproduced – this is how the film looked in the cinema.

There is only one soundtrack on offer and that's Dolby 2.0 stereo. Though a decent enough job in terms of clarity, this a film that screams out for a 5.1 track, its excellent use of sourced rock tracks and traditional Turkish music needing the subwoofer wallop and all-around assault that 5.1 can provide. The stereo track will do, but this would be a good time to engage those home cinema DSP modes.

It should be noted that the German DVD has the desired 5.1 track, but no English subtitles. Groan.

The principal extra here is a commentary track by director Fatih Akin and his regular editor Andrew Bird. The commentary is conducted in English and is a lively one – Akin's English is first rate and Bird is English by birth, and the two are obviously good friends as well as colleagues. Plenty of revealing background information is supplied on the locations (Cahit is collecting bottles in the very club in which Akin once did likewise), the main actors (Ünel is drunk for real in one scene), the supporting players (Akin's brother and a friend of his Mum play key roles), Turkish family customs ("I hate these kind of weddings"), and the technical aspects of filming. I was genuinely astonished to hear that the film was shot entirely hand-held, a real testament to cinematographer Rainer Klausmann 's extraordinarily steady hand. There is also a solid awareness of the film work of others, including an admiration for Ken Loach and a suspicion that Tarantino uses his movie soundtracks as a personal juke box. A quick discussion on the fate of West Ham at the end provides a recording date (the team have done rather well in the past year), and I laughed out loud at Akin's admiration for Ünel's looks: "If I would be gay, I don't know, I would really eat him up!"

The theatrical trailer (1:51) is non-anamorphic 1.85:1, rather well put together and surprising in its inclusion of very strong language.

Finally we have The Evil Old Songs (5:58), Fatih Akin's segment of the 2004 project multi-director film project Visions of Europe (other directors involved included Tony Gatlif, Peter Greenaway and Aki Kurismaki). Anamorphic 1.85:1 and Dolby 2.0 stereo, the transfer is very good, but the film itself requires some interpretation and cultural knowledge to properly appreciate. It is intriguing enough to make me want to see the others in the project, though.

A trailer reel featuring promos for Untold Scandal, Brothers and The Miracle of Bern.

Beautifully structured and performed and utterly gripping from its opening frames, Head-On is an important film not just for German cinema but also for Turkish. As a drama of love, loss and cultural identity it knocks most other recent wanderings into any of these territories out of the ball park.

Soda's region 2 DVD is a largely fine affair, with a good picture and a very enjoyable commentary track. Only the lack of a 5.1 soundtrack irks at all, but I'll live with it. Highly recommended.

* According to director Fatih Akin on the commentary track, Ünel was indeed something of a slave to drink and was forced to kick the booze on medical advice during the shoot lest it kill him.