The best - meaning scariest - horror films leave the deepest chills to the imagination.

“The Uninvited” (1944) comes to mind.

So, too, do “Poltergeist,” “The Exorcist,” “Don’t Look Now” and “Carrie,” before it’s final fright got rehashed in so many other films it became a cliche.

All of those movies were heavy on atmosphere, light on special effects and CGI.

Most contemporary frighteners (Michael J. Fox’s “The Frighteners” is a good mix of humor and scares) opt for flash and noise, accompanied by an appropriate orchestral soundtrack that telegraphs every wisp of spookiness.

Each also comes with a paint-by-numbers story line.

“The Reapng,” a new supernatural thriller that gives Hilary Swank a break between challenging roles, does the atmosphere right and provides one clever twist.

Otherwise it’s: been there, done that.

In modern-day Louisiana, Swank plays a former minister who gave up on God after her husband and daughter were killed on a mission.

Now an investigator who disproves miracles and writes about it, she’s asked to come to the tiny Bible Belt town of Haven, where a river’s turned red and a spooky little girl with blond hair and big round eyes is accused of causing it - and of killing her brother, whose body shows no signs of foul play.

The townspeople, all white, clean and devout, fear the river has been turned to blood, signaling the first of the Biblical 10 plagues (frogs, locusts, death of first born, increased taxes).

They want Hilary to prove them right - or wrong.

And so the story goes from there, with eerie swampland settings, familiar dreamlike hallucinations, escalating unexplained phenomena - and a saga that proceeds exactly as you would imagine - except in the homestretch.

Swank ranges from skeptical to anxious; no middle ground.

The primary problem: Nothing’s left to the imagination except for the aforementioned plot twist.

Not that the special effects aren’t cool; it’s just that they’re all spelled out in front of you, and nothing’s left to the imagination.

“The Reaping” is not awful; if you like supernatural movies with strong religious undertones, or in this case overtones, you will probably have an OK ride.

But take it at matinee prices. Or, better yet, wait to rent it on video.

Even better, rent one of the classics mentioned above.

And watch it late at night, alone, in the dark. Ooooooooo, very scary.