I had become interested in this movie because of the director and an interest in Asian crime movies. It involves a young former detective with a background in psychoanalysis turned professor helping out with the investigation of an unsolved case of a murdered family. In the meantime a creepy weirdo moves in as his neighbour, who gives odd, contradictory signals, but ends up getting close to the protagonist and his wife in a relatively ordinary neighbourly relationship, while still being weird and regularly thoroughly creepy. It is obvious that the movie is structured towards the revelation of the guy having something to do with the unsolved case, simply by the focus that is put on the interaction between him and the detective and his wife.
So far it's okay, and one would like to watch how it ends, however as perhaps too commonly with thriller-type or crime movies, especially with a hint of horror, the writing has frustrating aspects and is often positively baffling. Problems are artificially introduced, left unresolved and drawn out so that the film will have a full run-time. Characters behave in the most pointless, unintelligent ways, but only at crucial moments. This is typically related to an unparalleled lack of communicative or reasoning ability, coupled with an uncooperative or impatient colleague/super/witness/loved one etc.
More particularly in this case, the detective's wife is first creeped out by and careful about the neighbour, while trying to stay friendly to him, however when the relationship gets only slightly better, it is indicated that she seems somehow positively intrigued by him on a personal level, although there is no lack of creepiness and awkwardness of interaction, aside from a conspicuous absence of the neighbour's supposed wife (supposedly because of a depression), and although the detective is a perfectly good guy and there is no real issue in their relationship (in fact there is not much of any emotion or relationship drama in this movie).
More than that, the detective himself is strangely reluctant and inconsistent at following his "intuition" about the guy and simply ignores and doesn't mention to his wife that the neighbour's supposed "daughter" came to him and said it is not really her father but a complete stranger... Apparently casually dismissing this as merely eccentric behaviour or a joke of the girl, while merely vaguely hinting at it to his wife as something that "creeped him out".
And when the detective turned professor finally points a colleague towards the investigation of the neighbour, and this colleague quite foolishly directly turns up for an interview at his place, and then immediately turns up as a burn victim next to the two other people who died in the fire in the house right next to the detective and the creep, he fails to mention to the superior investigator that he had pointed him towards the creep (and of course has no relation to the other dead family) but instead merely mentions that the neighbour had the TV on while the fire was raging (which is deemed far too indifferent).
When he later mentions it after all, the superior ignores it simply (angrily, for some reason, what else).
In addition to this, a witness of the unsolved case is annoyingly uncooperative and uncommunicative, always running away, and unwilling to simply look at a picture and say if she knows the person. Her avoiding behaviour and inability to even stand (the f-- -) still almost makes one want to smack her as a viewer, however it also shows a communicative inability and overindulgence of those interacting with her.
Unfortunately that is just the beginning of the oddities, after this it becomes almost completely random.
Such issues of lack of intelligence come down to foolish writing and are simply frustrating, decreasing the quality of the movie, which otherwise is competently shot and acted.