– This review contains some spoilers, so proceed with caution –

Ah, the Catholic church. To those of us not shackled by the dogmatic constraints of faith and ritual, much of what goes on within its walls can seem abstract and peculiar and its intransigent attitude on certain key social issues baffling. Every now and then, a film comes along that, pre-release press informs us, has upset this mighty organisation, met with its disapproval, though even these days it doesn't seem to take that much. The slightest dig and the cries of protest start flying, and recently the claim from within has been that anti-Catholicism has become the new anti-semitism. But after centuries of international wealth and power, the Spanish Inquisition, the Magdalene Laundries, the effective suppression through dogma of free thought in countries where the church holds sway, not to mention a whole string of recent scandals involving priests and young boys, they've got some balls. The church remains hyper-sensitive about its image and reacts badly to being openly questioned about its habits, however justified the attack and shady the secret. The Crime of Padre Amaro arrived so criticised, but to be honest is hardly going to bring the church to its knees. A critique it certainly is, but a full-scale attack it most definitely is not.

Although much of the narrative is rooted in truth, the screenplay itself is adapted from a novel by Eca de Queiroz and was set in 1875 Portugal. The story goes like this. Young, good-looking Padre Amaro, a rising star in the church and a personal favourite of the Bishop, arrives in Los Reyes to work with old hand Padre Benito. Contrary to his vow of celibacy, Benito has been having a long-standing affair with local restaurant owner Sanjuanera, whose beautiful daughter Amelia soon catches Amaro's eye and confessional ear. Eventually, the two embark on a secret affair of their own, one that could threaten Amaro's standing in the community and the church.

The Crime of Padre Amaro is a title that provides forewarning of plot developments to come and in some ways this is exactly what the film delivers, though what actually constitutes the crime in question is not so clear cut. There are several potential candidates – moral, ethical, ecumenical and even legal – all of which the film attempts to explore. In a similar vein, potshots are taken at a whole range of clerical issues, which should make for a complex, multi-layered dissection of church mores and morals. But for a variety of reasons, it doesn't quite come off.

The issue of celibacy in the priesthood, central to the film's narrative, may not be at the top of the Catholic controversy chart, but it's still a subject for debate within religious circles and indeed is under discussion by a gathered priestly group early on in the film. The celibate Amaro suggests a voluntary approach, while Benito, who is (we presume) being given a regular seeing-to by Sanjuanera, angrily affirms the importance of such a behavioural restriction. (That the whole celibacy issue came about largely because the church was fed up with the widows and children of priests inheriting their land and property and then turning their back on the church is, of course, another thing entirely.) What starts as an examination of the problems of enforcing celibacy on the priesthood becomes a comment on clerical hypocrisy. Other targets include the link between the church and organised crime, the dangers of pushing abortion underground, and the division between the image-conscious church hierarchy and the more politically active ground troops. It's worthy stuff, decently made, but whether it hits hard enough, or delivers its message in a convincing way, is another matter.

Despite the setting and moments of genuine originality and narrative efficiency, formula is too often at work here and drama eventually gives way to melodrama. Consider the opening scenes. Amaro is en route to Los Reyes by coach when it is stopped by two young hijackers, who storm through the bus with guns, rob its passengers and disappear into the night. The scene is brief, pacy and unfussy, and that both the film and the bus move on without comment tells us much about the social situation in which Amaro will be operating. As the bus reaches its destination, Amaro gives money the robbers missed to the old man sitting next to him, who lost everything in the incident. Just four minutes into the film and we know who Amaro is, why he is traveling to Los Reyes, and that he is a kind-hearted and generous man. I, for one, was impressed by this filmic economy. And then, as the good-looking young Amaro steps off the bus and takes stock of the location, we immediately cut to equally good-looking Amelia walking jauntily out of the shadows, and in the space of two seconds I had much of the next hour of the film plotted out, confirmed beyond doubt when Amaro asks Amelia for directions and an "ooo, isn't he nice!" look crosses her face. From then on it's all a matter of time.

What keeps interest ticking over is the small detail and the sometimes quirky supporting characters. As Amaro first enters his new church, our ears are assaulted not by a heavenly choir but the extraordinary musical wailings of the town's resident cranky old woman, Dionisia. (As a side-note, while on DVD this plays as amusingly strange, in the cinema it prompted gales of laughter – such moments come alive with an audience and are best viewed that way.) Initially intriguing and rather amusing, she later represents one of the problems with the film. As a devout Catholic who scolds children for treating the communion host as snacks and yet feeds them to her cat, or who leads a mob to throw stones at the house of a local heretic yet arranges an illegal abortion for money, she is something a contradiction. This may, of course, be director Carlos Carrera's point, it just feels a little clunky. Other characters are nicely sketched with interesting stories that are given too little exposure. Ruben's father, Don Paco, is a man with a genuine hatred for the clergy and the film's most unexpected character and one I immediately warmed to, while the politically active Padre Natalio, who repeatedly defies his Bishop and is the only priest in the film who is genuinely committed to his calling, deserves a movie all of his own. This one, actually. He is at his most engaging when he refuses to toe the clerical line at a moment that will prove critical for his career. "It's an order from your Bishop," Amaro warns him. "I don't give a shit," he smilingly responds. Even the Bishop himself is something of a character, though it was he who prompted the film's only unintentional laughs on my part, specifically when a jovial discussion is brought thoroughly down to earth by a phone call from him, reminding me rather unfortunately of the fearsome Bishop Brennan in Father Ted. This was emphasised in a later scene when the Bishop is sitting in a bath barking instructions to Amaro via a mobile phone in classic Brennan mode, something that extends to the dialogue: "You must deliver it to him personally," the Bishop tells Amaro of an excommunication order destined for Padre Natalio, adding, "Either he gives in, or he's fucked!"

Given this interesting background detail, its something of a shame that the central characters and much of the narrative are so obviously drawn. Amaro and Amelia's story consists of a few too many familiar plot turns, and their characters are ultimately too shallow to invoke the sort of emotional response that the narrative demands. Having announced the impending relationship so obviously in the opening five minutes, the film them borrows from a variety of sometimes surprising sources: the secret love affair, the inevitable betrayal and eventual pregnancy are all by the numbers, and Amaro himself goes through a sometimes Jack Torrence-like series of metamorphoses. The kindly young priest of the opening scene becomes, when calmly laying things on the line to a newspaper editor, Michael Corleone from The Godfather, then later, with his selfish attitude to Amelia's pregnancy and cold suggestion of abortion is more like Michael Caine's Alfie. For a man who has only just wandered from the path of celibacy, he learns bad habits as if born to them, turning from selfish git to woman-beater in a flash, though he immediately and predictably breaks down in horror at what he has done and is becoming. The aim is, of course, to show that this man is prepared to put himself and his ambitions above everything, including love, death and friendship, but saddled with stock situations and borrowings, and lacking the burning anger of a film like Peter Mullan's The Magdalene Sisters, the attacks fall a little flat.

Old stories in new settings are evident in other areas of the film as well. Ruben, Amelia's boyfriend, inevitably loses her to the handsome newcomer, but that's what supporting role boyfriends are there for in modern mainstream narratives, and when this fledgling reporter has to choose between loyalty to his home town and the Big Story, there are no prizes for guessing which one he plumps for. Similarly, Padre Benito's relationship with the local drug lord is on the whole familiar Catholic/gangster stuff, including the photographer who is stabbed by someone who doesn't like having his picture taken (though this attacker may be more than he seems). And so on.

As I said earlier, there are still enough character details to hold the interest and the performances are on the whole enjoyable, with Gael García Bernal once again proving to be Mexico's most enigmatic new star, even if this finds him in low gear after his terrific performances in Amores perros and Y tu mamé también. But the reliance on stock characters and situations and the decision to nibble rather than bite takes the edge off of the film's fine intentions.

All of this, good and bad, was highlighted on the second viewing, but the third presented me with some interesting issues. Watching with the commentary track on is an education in itself, as director Carlos Carrera outlines just how many story and character details are based on fact. This can't help but prompt you to look at the film in a new light, but reservations remain, as – opening bus-jacking aside – this doesn't really come through in the drama itself. This does mean that, thanks to the commentary, the film does play differently on DVD than in the cinema.

Framed at 1.85:1 and anamorphically enhanced for widescreen TVs, this is a first rate transfer, and especially pleasing for a foreign language release. Colours are solid, sharpness is bang on and the contrast is excellent throughout. No distracting picture artefacts are evident, and picture is free of dust spots and scratches. A very nice job.

The Dolby Digital 5.1 soundtrack is for the most part functional rather than spectacular – this isn't Die Hard, after all – but kicks ass when it needs to: the baptismal party hosted by the town's philanthropic drug lord throws music around the room and has the subwoofer bouncing around the floor. Also included are 5.1 Italian and English dubs, which are absolutely to be avoided – the English dub in particular is clunky affair.

The key extra here is a commentary track by director Carlos Carrera and leading man Gael García Bernal. This has already had a mention in the review above and with good reason, as the amount of background information given about incidents, characters and small detail in the film are so good that this proved to be a balance-tipper for me – having seen the film in the cinema and hired it on DVD, the commentary was good enough to prompt a purchase, especially as it can be picked up rather cheaply at the moment. The two men have a fine rapport and there are no dead spots of more than a few seconds, and really do give an extra dimension to the film, making it hard to see it the same way after listening to the facts behind the story. There are also some very nice actor/director bits, my favourite being the rather intense disagreement between them over whether Amaro told the whole truth to his Bishop regarding what he had done. Carrera also provides some background to the reasons for the film's controversy, and the pressure exerted by Catholic and conservative groups in some countries to suppress both the film, and any good word being written about it. The commentary is conducted in Spanish with English subtitles.

The making-of featurette is actually an EPK targeted at the American market and starts woefully with an idiotic American 'trailer' voice telling you that the film is about "A man caught between his heart's desire....and his soul's belief." More such crap comes thick and fast as this ludicrous voice-over tells us what a splendid thing this film will be. His script is hilarious, and this extra tells us little about the making of the film and functions more as an extended trailer. It is non-anamorphic 16:9 and Dolby 2.0, runs for 5 minutes and has (surprisingly) English and Italian subtitles.

Poster explorations has reproductions of six of the posters used to advertise the film.

There are filmographies of the director, the producers, the screenwriter and the two lead actors, and buried within are very brief interviews with the director and actors, shot 4:3 on grubby DV. All have English and Italian subtitles.

Finally there are two trailers, the first narrated by trailer voice man, the second initially set to music not in the film and, frankly, rather more interesting and seductive, that is until trailer voice man steps in again. Both are targeted at the American market and in some ways are rare for including dialogue (US distributors are notorious for trying to hide the fact that a film is not in English).

Tricky one, this. There's good stuff here, but it's let down quite a bit by a reliance on melodrama and formula, resulting in a high degree of narrative and character predictability. Catholics may be offended, but that have no real reason to be, as considering the ammunition available, the film lets the church off with a slapped wrist, being more interested in Amaro the man than Amaro the priest. Despite my reservations, the DVD comes cautiously recommended, for its picture, sound and a very fine and informative commentary track. If you rent the disc and are left unmoved by the film itself, give the commentary a spin anyway – it'll probably change how you see much of what happens within.