So ... What was the point of the whole movie ?

yes in fact she see the future and that is the twist and turn of the movie i liked it a lot

SPOILERS

the twist was that the ghostly people she saw were actually images from the future, rather than flashes from the past (which means the murder scene at the beginning was mostly a red herring). the visions drove her crazy cos she had no idea what she was seeing. fortunately for her editor and husband, the visions made for a bestselling book. Peck and the gardener girl were locals whom the husband hired to spook Susan (but Peck got killed accidentally at the end of the last vision).

i thought the plot was halfway decent, but the execution of the visions left more to be desired. if they were going for "natural" visions (i.e. indistinguishable whether they were visions or actual reality), those scenes needed to look less contrived (esp the "soccer kid"). the acting for the visions was really terrible... not haunting or frightening, just really badly done. the premise was just very poorly executed, and the unusually fast/nonchalant cuts from vision to real life made it very confusing for the viewers (esp those used to the hollywood-tell-it-straight style).

overall, the atmosphere could've used more a suspenseful build up, some kind of visual cue to indicate Susan's gradually deteriorating state of mind (well, aside from her hair getting slightly messier), while the denouement could've been less rushed, and more deliberate in distinguishing the husband-conspirators from the foretold-murderer/victims. the "news voiceover" just seemed so haphazard, i'm almost certain it was only put in after test audiences failed to identify the end-scene murderer as the same one from the initial-scene murders.

the point of the movie was to keep the viewer guessing whether Susan's visions were of real spirits, perhaps from the initial-scene's murder; or were they merely hallucinations caused by stress of book deadline / being alone in a big lonely house / Peck's "herbs"; or were the "visions" hired actors and part of the husband's conspiracy with Peck and gardener-girl. the twist, as mentioned, is that the visions were not of the past, not hallucinations, not even part of husband's plot; but actual prescient visions of the end-scene murder. unfortunately, the visions were badly handled, and the suspense mostly absent / obscured by distracting scenes.