Just watched - for the fourth or fifth time - this excellent minor ghost story from director Hideo Nakata, best known for directing the famous Ring. There's a strong family resemblance between the two films, but the overall approach is rather different. Dark Water offers a rather bleak and damp view of life in Japan.
The world of recently-divorced single mother Yoshimi is one beset by troubles, not least a custody battle for her beloved daughter Ikuko. When they move into a new apartment in a run down building Yoshimi is dismayed both by the water seeping through her ceiling and strange experiences that seem to focus on Ikuko. Some of the standard tricks of J-horror are used to good effect, though they are now over-familiar. There's the shadow on the elevator CCTV image, for instance.
The plot is well-handled and the main characters are sympathetic. The performance of tiny Rio Kanno as Ikuko is very engaging and as her mother Hitomi Kuroki manages just the right combination of courage and vulnerability. The actual ghost is of a familiar sort, but the film's climax and its aftermath are satisfying. This is one to rent if you haven't seen it.