Everyone was so excited about The Ring when it came out that Gloria and and I, who don't mind a good scary movie, rented both The Ring and Ringu back in early 2003. I thought Ringu was really scary, and still do. I wasn't really excited by the ads for The Ring 2, though, and we didn't go to see it. Every once in a while, I'd see "Ring Zero" on the shelf at the Asian imported DVD place in the mall, but I avoided that, too.
Today, though, we decided to make it a Super Ringy Day. We went to 48 Hours and Blockbuster and picked up Rasen, Ringu 2, Ringu 0, and The Ring 2. It's a little confusing, so I'll spell out as much as I know.
Koji Suzuki wrote a trilogy of books, Ring, Spiral, and Loop. I've read the first two, but the third has yet to come out in English translation. (It was due out in May, but has apparently been delayed.) The books have spawned a lot of adaptations. The first one that we saw was Ringu, which was orginally released as a double feature with Rasen. Rasen is Japanese for Spiral, and the movie was a pretty close adaptation of the book.
Japanese audiences apparently really liked Ringu but really didn't like Rasen, so the cast and crew was brought together to make a new sequel. This wouldn't be a third movie, but an alternate second movie. That alternate second movie was Ringu 2. A few years later, a prequel was made, Ringu 0. Ringu 0 was loosely based on a short story by Suzuki.
Shortly, television series show up: Rasen and Ring: The Final Chapter. (I think.)
A few years yet later, the whole thing spreads to America in the movie The Ring, which later gets its own sequel, The Ring 2, which has an original plot.
Like the Ring virus in the book, the plotline continues to mutate, changing slightly from iteration to iteration and spreading by different media. There are Ringu manga, now. I imagine that in Japan one can come by Ringu lunch boxes, Ringu "personal masage wands," and Rasen-branded well-water-flavored gummi candies.
We're in the middle of The Ring 2, right now, and have yet to watch Ringu 0. So far, I think that Ringu and Rasen are the best of it. I don't think we're going to see a movie of Loop, sadly. I just hope I get to read it.