It’s often hard to know who exactly the joke’s on in “Fear the Night,” an unpleasant home invasion thriller about a break-in at a bachelorette party in the California hills. Maggie Q stars as Tess, a disaffected military vet who must take out some white trash after they break into her family’s farmhouse, where she and her sisters Beth (Kat Foster) and Rose (Highdee Kuan) have gathered to celebrate Rose before she gets married.

Most of “Fear the Night” dwells on the ambient fear and annoyance that surrounds Tess as she and her fellow partygoers try to escape without being raped and/or killed. Eventually, it becomes hard to tell if the movie and its canned culture clash/battle of the sexes drama is just self-consciously tedious or also hatefully ungenerous (to the viewers, the actors, the characters, you name it). One character tellingly accuses the other of “slumming,” so it’s perhaps worth noting that “Fear the Night” was written and directed by playwright Neal LaBute, whose recent credits include last year’s bloodless erotic vampire pic “House of Darkness.”

With “Fear the Night,” LaBute clearly aims to push viewers’ buttons, especially using the oft-repeated threat of sexual violence. Some dramatic irony mildly re-casts the movie’s otherwise formulaic conflict in a harsher light, but not much gets complicated by this extra knowledge, especially not LaBute’s tin-eared dialogue nor his indifferent direction.

In theory, Tess and Beth’s relationship underlines the tension of the movie’s primary event: the siege of the family farm by a trio of woman-hating good ol’ boys, led by Bart (James Carpinello) and Perry (Travis Hammer). These guys raid the house and kill a key guest with a bow and arrow. Meanwhile, Tess tries to save the day while also not murdering her sister, who obviously knows more about why Perry and his friends have targeted their house. Beth is often breathtakingly irritating, whether she’s snippily asking Tess not to curse in front of her daughter or off-handedly telling Tess to relax and have a drink, despite knowing that Tess has been sober for some weeks.

Tess’s wounded warrior schtick suggests that some things are sacred, despite the drama’s prevailing moral relativity. Other character tics and tropes are either sent up and/or negligibly complicated. It’s sometimes hard to see a difference when so many women in this movie reflect LaBute’s disinterest in developing believable characters. Rose’s guests all talk like helpless, horny caricatures, while Perry and the gang only talk about what these women “deserve,” especially rape.

That omnipresent threat isn’t necessarily unrealistic, nor is Beth and her friends’ by-the-numbers sassiness. Rather, a general lack of imagination makes “Fear the Night” a chore to watch, especially given how thin so much of Tess’s dialogue tends to be. Because if she’s the audience’s surrogate, then it’s hard to imagine that there’s a point to this much nudge-nudge genre pandering, not when the bachelorettes lay into an attacker in front of a big “Same Penis Forever” party banner, nor during Perry and Bart’s frequent and empty taunts. At one point, a bad guy asks a bad girl if she’s going to let “a black chick” tell her what to do. The black chick in question, played by Ito Aghayere, somehow doesn’t respond until she flirtatiously and laboriously offers to have oral sex with one of the attackers. Everything is bait in “Fear the Night,” but none of it is worth taking.

“Fear the Night” might have succeeded as a cheap but thrilling work of post-feminist revanchism. Some bloody violence does not, however, add much to the movie’s empty you-go-girl rallying around Tess, which is as deadly serious and unconvincing as “Fear the Night” gets. A lot of dead air and placeholder repartee also suggests that there’s no great distinction to be made between the type of movie that LaBute might be sending up and the one he wound up making.

In a tellingly awkward establishing scene, LaBute struggles to establish that Tess has an edgy sense of humor. She describes herself to Beth’s friends as a teacher, or “Mr. Miyagi with tits.” Silence. Tess continues anyway: “What’s not landing for you, Miyagi or tits?” Because she’s Asian-American, and they’re not, right? This gag’s tone is ostensibly tongue-in-cheek, but that two-part line is flop-sweat clammy.

“Fear the Night” often feels like it was made by artists who understand the type of movie that they’re making but maybe don’t really care enough about making it, either as a by-the-numbers genre exercise or a repudiation of its fans and their need for pseudo-enlightened catharsis. Rather than pick a lane, Labute and the gang cruise down a flat, weirdly empty stretch of well-trod road. Good luck to both the curious and unsuspecting viewers who follow them.

Now playing in theaters.