“Shady Grove” is another “city folks trapped in a cabin in the woods” tale, this one with a pregnant couple partying with their best friend, when a demonic cult interferes. You know how demonic cults are about pregnant women.

It’s a cumbersome, lumbering thriller that fails to build suspense or much in the way of horrific momentum. The filmmakers are more invested in sex-in-the-shower scenes and cute banter than the perfunctory killing to come.

Throw in some indifferent acting — few people summon up any sense of terror — and you’ve got yourself a loser, even if the film’s a take-off on the ill-fated rural romance of that famous old folk song that gives the community where all this takes place its name.

Niki McElroy (who co-wrote this) and Todd Anthony are a couple that’s just gotten back together long enough for her to get pregnant and him to get over her brief lesbian dalliance. Juhahn Jones plays Eli, their on-the-make pal, the one that invites some pretty locals for a fireside party at their rental in the forest.

But as the dark settles in and the paranoia over “that smell” coming from the locked pantry grows, the burlap deer-antlered hoods come out. Let the wild rumpus start.

Comic actor Jones of “The Starving Games” and “You Married Dat” has young Chris Tucker energy that he shows off in flinging lame come-on lines at every woman in sight and “Mr. Light-Skinned-Man…thinks he’s a Cherokee” zingers at his best friend.

Victoria Baldesarra makes a pretty villainess, and a pretty uninteresting one.

The action is stunningly static, the murders something of an afterthought and the logic illogical, starting with the “smores” campfire party being set in broad daylight.

And the slaughter, when it finally starts in earnest, is by-the-book and dull and features the fakest looking blood this side of Heinz 57.

Rating: Unrated, graphic violence, sexual situations

Cast: Niki McElroy, Todd Anthony, Juhahn Jones, Jackie Ritz, Becky Hayes and Victoria Baldesarra

Credits: Directed by Dale Resteghini, scripted by Nathan Dalton and Niki McElroy. A Gravitas Ventures release.

Running time: 1:35