Although Spiral contradicts many things in the original film ringu it is actually based on the sequel book written by the original author of Ringu. He also worked closely with the director when making Spiral. He actually wrote three books in total but the third hasn't been made into a film probably due to the lack of popularity of spiral. If anything this version/universe of Ringu is more to what the author intended and is not an awful film I thought it had quite a good plot twist at the end, however it isn't wholly satisfying as it does contradict the original to much and takes away most of the horror aspect of Sadako. I think it should be appreciated as it is a well made film and is based on the authors original intentions as a sequel to the Ringu he created in his original novel and not despised as an attempt at a sequel just made up by this director as that isn't the case.
