Unconditional

Screen newcomers Harry McEntire and Madeline Clark - as 16-year-old twins Owen and Kristen - are reason enough to watch this atmospheric and unsettling if not entirely successful debut from long-time TV director Bryn Higgins. Even when the plot, from The Tichborne Claimant writer Joe Fisher, begins to spin out of control, McEntire, in particular, keeps you involved and Clark would no doubt do so too, were she not ill-advisedly sidelined by the script at that point. Of all the new names at this year's Edinburgh Film Festival, these two are definitely the ones to watch out for in future.

Owen and Kristen are Newcastle-based teens, living in high-rise flats and just about getting by as they care for their wheelchair-user mum (Melanie Hill). Although the kids lament their lot and banter about the fact that "she's fucked", the family share a close bond and key emotionally charged moments between McEntire and Hill provide heart for the movie.

The relationship between the twins is threatened, however, when Kristen brings charismatic loan shark Liam (Christian Cooke) into their orbit. Initially, it seems that Kristen's romantic inclinations might be reciprocated but it soon becomes apparent that Liam's interests lie in an altogether less conventional direction. Taking Owen for a lads' night out, he plies the youngster with drink before, on returning to his waterside apartment, suggesting that the teenager dress up as a woman "for a laugh".

Owen's enthralled acquiescence sparks a shift in their relationship as Liam, increasingly obsessed with Owen - whom he prefers to refer to as Kristen ("I don't snog boys, I'm not deviant. Get changed.") - starts to look like a serious threat.

Higgins' film is at its best in the early stages, when brooding threat is mixed with Owen's general sense of confusion about his sexuality and the tension between his attraction toward Liam, his fears about his relationship with his sister and a nagging suspicion that he's getting in too deep. The fine-featured McEntire makes a very convincing 'girl' and he retains sympathy to the last.

Once Liam starts to become dangerously unhinged, the plot slithers away from believable territory. Owen may be disoriented by his conflicted feelings but by this time we know he's a sensible lad who would surely be thinking of running a mile from this nutjob. The use of transvestism also feels rather pat and exploitative, litle more than an easy plot device to emphasise Liam's obsession rather than an idea that the film wants to examine in its own right.

With Owen's mum and sister virtually dropped from the story, the narrative is all cross-dressed up with nowhere to go, and Cooke is forced to maintain a scenery-chewing level of rage that goes on too long without respite. Having notched up the emotions, Fisher just sits back and lets them boil away what's left of the plot's believability, although you stay with the actors to the end despite the film's failings.