Question: When is a horror film not a horror film? Answer: When it’s a supernatural thriller. Or so Warner Bros. and its advertising team would have you believe. For though The Reaping contains biblical curses, possessed children, occult sacrifice, and rivers of blood, it stops just short of horror. Its thrills, such as they are, are strictly of the supernatural variety.

The first film since The Abominable Dr. Phibes to take the ten Egyptian plagues and use them as an opportunity for terror, The Reaping accomplishes the impossible: it makes the wrath of God look boring. Plucked from their native biblical habitat, the plagues run rampant in the sleepy (and entirely fictitious) Southern town of Haven. At the center of them all is a frail, mute girl (Anna Sophia Robb) who seems to be the one causing the ruckus.

Call in Katherine Winter (Hilary Swank) to examine the evidence. An investigator of so-called religious phenomena (not unlike the “miracle killer” Ed Harris played in The Third Miracle), Katherine rejected her Christian faith after a village chieftain killed her family while on the mission field in Africa. She now travels the world with her trusty cameraman (Idris Elba) debunking the inexplicable. A handsome stranger (David Morrissey) comes to her requesting answers as to why the town’s water suddenly turned to blood. There is no scientific explanation. Katherine is given cause to doubt her doubt in God.

Despite the ingenious setup, it’s sad to report that The Reaping is a con job all the way, less interested in exploring the nebulous regions of the soul than meting out horror clichés in dispiriting detail. You know the drill: the creepy midnight walks, the telegraphed “gotcha!” moments, the odd pops and screams on the soundtrack, the familiar stock lines (“You’re in great danger”). Added bonuses include a casually condescending view of Bible Belt church culture (“Our Lord is a gentle Lord, but don’t push it”), child sacrifice, and a dismal, grainy-looking surface image.

The film tardily comes to life during a locust attack (the eighth plague, if you’re counting) in which swarms of digit-sized insects swirl poetically around Robb like critters out of a Grimm fairytale. The excitement lasts a solid two minutes.

Stephen Hopkins (Predator 2) directs with a steadfast instinct for commerciality. It may well reap a bundle. (Joel Silver’s name in the credits tells you as much.) Chad and Carey Hayes (House of Wax) wrote the screenplay, and claim the movie is about a woman’s return to faith. Granted. But isn’t it odd that there isn’t a single prayer uttered throughout the entire movie? Is it really so difficult to show a little passion where religious conviction is concerned? Isn’t it a sin to cast the magnificent Stephen Rea as a solemn priest and kill him off before the film is half-finished?

Like Katherine, I want answers.