First of all, I don't know why the notes / ratings here are so low - five is really so - so and this film is much better.
I did not really read the storyline of the film except that the woman is moving from New York to S Islands. So, that was what I knew and the rest of the film was interesting to me. It was rather on good pace. Not slow or too rushed. The acting was believable. The setting is good. The story is interesting and has some minor twists which are good. It keeps you guessing. I can not say that anything was predictable as many wrote.
I liked the movie. It was not really great and that blew me away, but for what it is - I give it eight!
Don't know whether because it is British, but the film kinda reminded me of those crime series from England my mother watches :) I don't know their names, but... somehow reminded me of that - and a bit of some Agatha Cristie movies.