My first reaction was one of disbelief and amusement. The production company is called Toilet Films, which had me initially fearing the worst. Instead, what I got was something altogether different. It didn't have me shielding my eyes in horror as the director intended, nor did it have me flushing it away as his company implies. I kept faith and sat through a good, but not great film.

Made in Korea, it seems well enough subtitled, but does require a good deal of concentration because, to the unfamiliar western eye, it is hard to keep track of the actors and the roles they are playing, as well as read the subtitling.

Director Byeong-ki Ahn calls it a genuine horror movie. I'm afraid he is delusional. The film does not qualify as horror, even if he slavishly follows all the protocols; it simply isn't scary enough, although the trailer might have you thinking otherwise, because they manage to splice together quite a shocking minute or two for that! What it turns into, however, is an intriguing supernatural thriller.

The director's use of music, a single spooky location, the menace of intrusive noises - in this case, the phone ringing - and a number of other horror conventions all contribute greatly to the atmosphere, as does the fact that he often shoots through glass, into mirrors, from behind glass and so on, so that nothing is quite as it seems. However, the film never gets truly edge-of-your-seat, knuckle-whitening frightening, although the premise of a rogue spirit in a mobile phone that drives people to the brink of madness does have the potential to take you there.

The central character, Ji-won (Ji-won Ha), a female journalist, is reassuringly robust, determined and resolved. She is surrounded by other fine female roles, played well by Yu-mi Kim and Ji-yeon Choi. It is nice to see parts like these for women in the cinema, where they provide the main focus of a film and drive the action forward, rather than the eponymous male hero. In Phone, the lone man may play a key role as far as the plot is concerned, but in terms of the film it is a peripheral one. But the most astonishing performance is given by Jeo-wei Eun, a small child of seven. Her depth and range in one so young is quite remarkable and puts many more famous American child actors to shame.

This is a pleasing psychological mystery, with a supernatural twist, and it does keep you intrigued and watching to the end for its suitably shocking denouement.