The Nesting is an open-ended supernatural thriller featuring a convincingly neurotic writer with a bad case of agoraphobia (among other things) who decides to rent a house she finds out in the country that looks suspiciously like the one featured on one of her book covers. At times the film is a reasonably intelligent thriller but it has a tendency to err on the side of goofiness. Many of the characters, despite being likable, are incredibly over the top (the Colonel, handyman Frank, etc) and quite often characters are brought into a scene solely to die because there aren't enough victims on-hand.
The film's ambiguity is largely owed to the fact that the ghost scenes only seem tooccur when the writer is nearby and the others seem to die right after the encounter. That and a later reference would almost suggest that the thing could have been in her head although the attacks look like they're being carried out by an invisible, supernatural assailant.
The writer's character is relatively dull, as are her two apparent romantic interests. Other characters are humorously colorful and bring a lot more to the production but the protagonist really seems to exist to do little other than unconvincingly act scared by various phenomena (oddly not done as well as the agoraphobia, but clever camera-work helped with that) and to unravel a mystery that never quite gets compelling.