Forgive me Father, I have lost the plot

Priest boasts a fine director, a great script-writer and a topical plot about a gay cleric. But Adam Mars-Jones is not converted

It isn't often that a British fiction film arrives on the screen just as the controversy over the issues it exploits - homosexuality and the clergy - suddenly comes to a rolling boil after simmering for months and even years. It must be enough to convince the makers of Priest, writer Jimmy McGovern and director Antonia Bird, that they are in the hands of a higher power.

This is a talented team (Cracker was first-rate television, and the Bird- directed Safe, broadcast in 1993, was rather better than that), but audiences of Priest are unlikely to feel safe in their hands. If you were to put together a "controversial" film on an interactive basis, with people voting on their phones ("If you think gay Catholic priests have the same obligation to celibacy as their straight counterparts, please press One..."), you might end up with something this muddled, full of the desire to take up a position, but capable in the end of offending virtually any shade of opinion.

Bird's first shot starts off looking down on a Liverpool priest in crisis - his dismissal and breakdown will make room for the film's hero Greg (Linus Roache) - and then cranes down so that it ends up level with his ankles and pointing upwards. Fair warning: the film will consider priests from the point of view of a pulpit, looking down, and also of a hassock, looking up. On the level of storyline, though, this amounts to hedging your bets - too bad-faith about faith.

If the Catholic Church is simply a human institution, then it has no right to make inhuman demands of its workers; but if a consecrated priest has supernatural power, then perhaps it does. The film has it both ways, by showing the utter irrelevance of the Church to the world of graffiti and the vertically mobile suspended urinals known as council-estate lifts, and then by showing the troubled priest working a miracle. It isn't a grand miracle - it involves the grill of a domestic cooker - and Greg doesn't even know that he's worked it as he kneels in his room in anguish, calling on the crucified Christ not just to "hang there" but to "do something". The impression of his intervention is created entirely by Bird's editing of the sequence, but we privileged ones in the audience are left in no doubt about the efficacy of prayer.

McGovern's screenplay was in three parts for television, and then four, before being reconstituted as a single theatrical feature. Useful information seems to have got lost along the way. When Greg ventures out to a gay bar, and goes home with the charming Graham (Robert Carlyle), is this his first experience of sex? Presumably not: he moves unhesitantly from the squeezy-nibbly to the penetrative. Nor is it a mechanical act. As their excitement mounts, the men's hands mesh, and we hear the Angelus bell on the soundtrack. The director, then, thinks that sex between men can have a sacramental aspect - but what does Greg think? When did he lose his virginity? Did he commit himself to God before he realised he was gay? Can we have a little background here, please? These are hardly side-issues. Greg isn't from Liverpool, but we don't know where he is from. Is it even planet Earth?

Greg's passage from self-oppression to self-acceptance is as mysterious and contradictory as the process whereby he changes from a dyed-in-the- wool Times reader to someone who refers to the Guardian in sermons. One moment he is scoffing paracetamol and wanting to end it all, the next he is coming up with glib little bits of gay-lib rhetoric to alienated straights who visit him in hospital ("you may find this extraordinary, Charlie, but you never really turned me on"). One moment he is embracing Graham wholeheartedly on a beach, the next he's refusing him the communion wafer because he knows that his mouth is defiled. One moment we're invited to think he is a gutless twerp for apologising to the congregation he feels he has failed, the next we're being set up for his redemption by human charity - hugs, tears and the dread arrival on the soundtrack of "You'll Never Walk Alone".

The last sequence of Priest is a sort of Rorschach plot of a resolution that means whatever you want it to mean. It could mean, these tears are proud, I will never again apologise for what I am or let the Church tell me who to love. It could mean, I have been selfish and weak, I will never again put my needs before those of my flock. It could even mean, the Pope is right on the money: celibacy is a hard rule but no harder for me than for anyone else. I will never see Graham again. Bird's camera now reverses the opening shot of the film, ascending again to stained-glass window height, having nailed its colours to a bewildering variety of masts.

It's a relief to turn from the cold opaque hero to his fellow priest Matthew (Tom Wilkinson), who's got all the right ideas. He is not happy- clappy, he is huggy-political, disillusioned and hopeful in just the right proportions. If you wanted to learn how to be gay, this warm straight priest could teach you. Then there's Cathy Tyson as the housekeeper, who is also Matthew's lover. Tyson is one of the finest, warmest presences in British acting, and unfortunately she is used here as just that, as a fine, warm presence. She smiles at that which is good and frowns at that which is bad. She is infallible. If emotion was a Church, she'd be Pope.

Jimmy McGovern's flair for comic dialogue is kept in the background of the script, delegated to minor characters, which gives the impression that every single person in Liverpool and environs has a rough, salty grasp of life's basics except for the person McGovern has chosen to make the centre of his film. In Liverpool they know that coffins are for dancing congas round, and even the policeman booking Greg for a sexual offence, on learning his occupation, merely murmurs "you little devil". The elderly housekeeper in the rural parish where Greg is sent in his disgrace gets her revenge on the sour Latin-speaking senior priest by serving roast pork in a "Meat Is Murder" apron. Despite such incidental pleasures, Priest can only really be recommended to people who have never heard the phrases "piss off" and "out of my diocese" in the same sentence, and are anxious to rectify the omission.