By Joshua knopp/managing editor

The writer and director of Saw have made a movie without shedding a drop of blood.

Insidious is a ghost story and a stark contrast to Leigh Wannell and James Wan’s famous gorenography series. Renai (Rose Byrne), a housewife and aspiring musician, begins to experience frightening supernatural events when her eldest son, Dalton (Ty Simpkins), returns home three months after falling into a coma. When she continues to be haunted after convincing the rest of the family to move with her, a psychic (Lin Shayne) determines that the focus of the paranormal events is not a particular location, but Dalton.

This movie has an awkward combination of subtlety and straightforwardness that manages to keep the audience guessing. The audience can see a scare coming from a minute or so away, but the scare still frightens through the magic of camera angles and a few dozen aggressive violins.

The cameras provide fantastic effect in Insidious with mobile cameras, point-of-view shots and Dutch angles used to full effect. Lighting is also used to its full advantage as the set uses muted colors and extremes of light and dark to create a movie that is not quite black and white but can still use color in scenes that aren’t trying to scare.

But even if the audience closed its eyes, the film would be at least unsettling. Joseph Bishara’s score, mainly of savage violins, adds more to the film than any original score since Psycho.

Unfortunately, the quality of Insidious lasts only through the first half of the film. Shayne’s overzealously played character breaks a cardinal rule of ghost stories at the end of the second act by explaining everything. At least three-quarters of the fear involved in these movies is the shadowy nature of the tormenting poltergeists. Once the audience understands their motives and the “rules” they operate by, the film becomes predictable on a scene-by-scene basis. It also doesn’t help that Shayne explains the “rules” in two overlong and poorly delivered monologues.

Insidious extends producer Oren Peli’s recent dominance of the haunted house/ghost story genre. Peli wrote and directed Paranormal Activity and produced Paranormal Activity 2 (which also explained “the rules”). Peli has directed and is producing Paranormal Activity 3, to be released in October, and is also producing Rob Zombie’s Lords of Salem (in pre-production).

While Shayne’s monologues herald a closing act that is just silly, Insidious features some fantastic camerawork and a haunting final image. It is a more-than-serviceable scary movie.