By and large, every horror subgenre relies heavily on setting and mood, so finding a great location is half the battle. Writer-director Brad Anderson (2008's "Transsiberian") outdid himself in this department with "Session 9," a methodically paced psychological chiller that starts slowly and ends with the viewer's heart racing. The film shakes and stirs in a way that few films do, exploring the most fragile and potentially bleak corners of the human mind. That Anderson manages such a feat not with violence, but through suggestion, editing, and the invaluable use of crackly voice-over recordings permeating over images both benign and threatening, shows what a firm grip he has on filmmaking. This is, to date, his most resounding cinematic achievement.

Hoping to receive a tidy bonus for their efforts, an asbestos cleaning crew headed by overworked new father Gordon (Peter Mullan) and right-hand man Phil (David Caruso) give their word that they'll be able to finish their three-week job at Massachusetts' abandoned Danvers State Hospital in only five days. It's a daunting proposition—the mental institution, erected in the 1870s, has been closed for fifteen years and is in crumbling, dilapidated shape—but one that Gordon is confident they will be able to pull off.

As the hours and days tick by in a place where untold amounts of tragedies and atrocities have occurred, the men's relationships and psyches gradually begin to crumble. For Gordon, he is faced with troubles at home and a rising mistrust in his co-workers after weasily hot-shot Hank (Josh Lucas) doesn't show up for work on Wednesday and allegedly has skipped town. Meanwhile, Gordon's wet-behind-the-ears nephew Jeff (Brendan Sexton III) tries not to let his uncle down, and Mike (Stephen Gevedon) becomes enraptured with listening to the case studies of now-deceased multiple personality sufferer Mary Hobbes after stumbling upon the doctor's recordings.

Shot on location at the sprawling real-life Danvers State Hospital—a building that infuriatingly was demolished in 2007 to make way for an apartment complex—"Session 9" is a sometimes brilliant study in restraint. Writer-director Brad Anderson and co-writer Stephen Geveden (who also essays the role of Mike) aim to scare their audience, but they do this by turning their backs on modern-day horror trappings and allowing their characters and story the room to breathe and develop in a natural fashion. Is the asylum haunted? Perhaps not in the conventional sense, but the pasts of the mentally insane patients who resided and often died there live on within the walls of the imposing structure. They also survive through the existing audio reels that Mike finds and listens to, the horrific tale of Mary Hobbes playing out over nine sessions that culminate in a revelation as truly unnerving as the one that occurs between the five men presently working there.

The ins and outs of the relationships of working crews is captured with a keen and provocative eye, offset by the sinking suspicion that something isn't quite right between them. With Gordon unable to hide how overextended he is with a new child and a rocky marriage, Phil grows worried about his abilities on the job. Gordon, in effect, questions Phil's ulterior motives, particularly after spotting him talking to two unknown men on the hospital's property and later finding him with a valuable coin that may or may not have come from a stash located in the walls of the underground tunneling system. When Jeff discovers the thought-to-be-gone Hank lurking incoherently in the stairwell, he is wise enough to know something far more ominous is going on.

The unique setting is the fifth and just as important character in "Session 9," director Anderson and cinematographer Uta Briesewitz (2007's "Walk Hard: The Dewey Cox Story") taking full advantage of their almost unearthly surroundings. From the patients' rooms, littered with old pictures stuck to the walls from decades' past; to the dank surgical areas, where lobotomies were performed; to the complex maze of tunnels underneath the building, the film's portentous atmosphere is thick enough to suffocate. All of these places and several others play a part in a third act as thought-provoking as it is veritably frightening. With the camera gliding along hallways, amidst the outside property, and from the sky, the picture's aesthetic style reminds favorably of Stanley Kubrick's 1980 classic "The Shining." Additionally, the music score by Climax Golden Twins is rich with the sorts of unidentifiable sounds and instruments that only add to the shiver-inducing tone.

The top-tier cast is as good as expected. Peter Mullan (2006's "Children of Men") runs off with the most glory—his character of Gordon is for all intents and purposes the lead, and also the most intricately layered—and he is exceptional as a man who either could be coming unhinged or just having a bad week. As Phil, David Caruso does nicely low-key work without all of the histrionics and silly voice inflections he uses on TV's "CSI: Miami." And Brendan Sexton III (2001's "Black Hawk Down") leaves an impression as Jeff, a normal kid having to work with people who look down on him because he's young and hasn't yet learned all the ropes.

Audiences expecting a more-of-the-same type of horror story may not latch onto or have the patience for the quietly rattling pleasures of "Session 9." Playing to a classier tune, the film is one that is immersive even in its understatedness, weaving a tale that is all the more effective because of how believable it is. Everything that happens could happen in the world we live in—some of them even did in Danvers State Hospital—and that's the scariest thought of all.