One of the most tense movies out there I'd really like to write this review without reference to the U.S. remake; "The Ring", but I guess that'd be ignoring a major influence on many people's desire to see this film. So I'll say this; "The Ring" is a poor schlocky Americanised film which takes a good idea and stamps it into a mediocre mold. "Ring" or "Ringu" is a very good film. If you're trying to decide which one to see, use that as your guide. In fact, an interesting point about the films can be summed up looking at the titles. "The Ring" has an added 'definite article' indicator; "The". This implies that the film is about a ring. It isn't. Enough said. There's a lot more ambiguity in the one-word translation of the Japanese film's title; "Ring". It's ambiguous, maybe even... thought provoking! I think that sums up the differences.
So, yes, Ring is a good, tense, movie. It runs almost like a detective story rather than a traditional horror film as the main character works her way closer to finding the facts behind the mysterious video tape. But all the while there's an ever-mounting tension as her numbered days expire. In this way it's reminiscent of Angel Heart, another dark, tense, supernatural detective story which demonstrates that the big American studios will sometimes make a good dark thriller. In fact, the tension, partly thanks to the minimal music and synthesizer noises as well as the excellent subdued lighting and camerawork, is the making of a film in which very little actually happens. Ring is a lesson in how to make an everyday cityscape seem scary and bleak while the addition of supernatural overtones, which I'm told weren't in the original books to the same extent, are a welcome addition and source of mystery. I suspect, although I cannot read Japanese, that the film is probably an improvement on the books.
Perhaps the main skill in creating a popular horror movie is to create a viable adversary. Sadako is perhaps the best example of this in film making. She is just a damp, bedraggled figure in an off-white night-dress whose hair obscures her features and who, as far as I can remember, isn't even seen until the last few minutes. Yet she invokes a real sense of menace, you know she is powerful and malevolent through the characters' reactions to her, even if she doesn't graphically do anything horrifying. Say "Sadako" to anyone who's seen the film and watch their face tense up for an instant.
So, should you watch this film? Yes.