Horror frequently proves to be one of cinemas most frustrating and difficult-to-master genres, such that when we happen to stumble across an even half-way decent entry, it tends to warrant attention. The Pact, a slow-burning investigative poltergeist pic, serves best as a calling card for director Nicholas McCarthy, who somewhat balances out his weaknesses as a writer with a strong visual instinct and knack for atmosphere. From practically minute one, all of the above becomes clear; the film is shot in a meticulous, almost grimly painterly style, but is sloppy when handling exposition, self-consciously doling out all the pre-requisites over a phone conversation. Annie (Caity Lotz) has arrived back in town to visit her deceased mothers house and family home, as her sister, Nicole (Agnes Bruckner), has disappeared, seemingly without a trace. Soon enough, Annie discovers that a troublesome family secret holds the key to her whereabouts. While it disappointingly gives way to convention and cliché in its latter two acts, the first half-hour of The Pact is a veritable masterclass in quietly-wound tension. The chilliness is perfectly pitched, not resorting to jump scares enforced by loud tension chords. Rather, an eerie acoustic guitar score reminiscent of John Carpenter creates an aural landscape for lengthy, dialogue-free scenes, guiding us through the slow build. Credit is also due to Lotz, a relative newcomer who will hopefully secure more and better work off the back of this. She credibly conveys the vulnerability of her character's predicament, and with an absentee father, dead mother and missing sister, her isolation. Annie has nobody but herself, and succeeds as a strong female protagonist, all the more when compared to most of her genre contemporaries. Act one is uneventful but absolutely functional; the creepy happenings and esoteric figures are hardly ground-breaking fare, but the enigmatic mystery and likable protagonist keep us compelled. By act two, The Pact explodes into Poltergeist-inspired thrills which are, given the restraint hitherto, almost disappointing. From this point, it does not hold many cards back, going the full measure of paranormal activity pretty early on. What truly underwhelms, though, is the shopworn detective angle, which relies on generic horror staples like flickering phones, Google Maps, and vague ghostly images. It is difficult to build true suspense with such automated attempts at keeping us compelled. Similarly, some surreal dream sequences feel derived from better horror films and simply do not get the blood pumping. Later on, things do perk up considerably with the appearance of Casper Van Dien in his first theatrical release since Tim Burtons 1999 Sleepy Hollow - as a ruggedly handsome cop trying to help Annie get to the bottom of this. Also, Haley Hudson is memorably, creepily effective as a spaced-out medium offering supernatural insights, though these moments only invite our protagonist to do more Googling which, again, is not conducive to upping the thrill factor. The longer the breadcrumb-following is stretched out, the more the sedate pace initially a welcome diversion begins to hurt the pics effectiveness. Interest is roused once again at the tail end, as compelling revelations lead us into the final stretch, which nevertheless resorts to placing Annie in a standard slasher set-up, as well as in a low-cut tank top, shot quite blatantly with male audience members well in mind. It respectably leaves vagaries to ponder, and there is ultimately some satisfaction to the climax, even if McCarthy cant seem to resist a pointless stinger. And that sort of encompasses a large part of the problem with The Pact - it begins very well and it ends servicably enough, but the puppy fat in the middle feels like it came from a different film. Despite its flakier elements, though, one sincerely hopes that Lotz and McCarthy secure more work as a result. A stylish and well-acted if disappointingly rote paranormal gumshoe story. The Pact is in UK cinemas tomorrow.