This was an OK movie, to be honest I expected more of Hideo Nakata, I worked out what was going on and why pretty early on in the film although if you think about it the opening credits pretty much give it away.
The thing that nearly spoiled this movie for me was the 10 years later epilogue, the movie should've ended on the final shot of the water tower.
I have the American remake of Dark Water somewhere so I might check that out sometime soon just to compare the two, to me this felt like a movie that was trying to appeal to an international audience and so a lot of the horror aspects were diluted in order to appeal to the broadest audience.
An OK movie with a lot of untapped potential.