(L-r)  Riley Keough, Christopher Abbott, Joel Edgerton, Kelvin Harrison Jr., Carmen Ejogo and Griffin Robert Faulkner in "It Comes at Night." MUST CREDIT:  Eric McNatt, A24
(L-r) Riley Keough, Christopher Abbott, Joel Edgerton, Kelvin Harrison Jr., Carmen Ejogo and Griffin Robert Faulkner in "It Comes at Night." MUST CREDIT: Eric McNatt, A24 Credit: Eric McNatt

Anyone expecting the movie It Comes at Night to live up — or, rather, down — to the self-consciously cheesy promise of its name, which hints at the kind of nocturnal boogeyman who has haunted so many horror films before it, must be unfamiliar with the work of its writer and director, Trey Edward Shults.

Shults’s only previous feature, the family drama Krisha, was not widely seen, despite garnering several nominations and awards for the first-time filmmaker. With that 2015 debut, about an addict attempting to reconnect with her estranged relatives, Shults demonstrated a flair for intense psychological confrontation — one that he puts into powerful new service in It Comes at Night.

The new film will feel familiar to fans of post-apocalyptic thrillers. Set in an isolated rustic home after some sort of plague appears to have wiped out much of humanity, the movie focuses intently on the relationship between two groups of survivors: Paul, his wife and their 17-year-old son (Joel Edgerton, Carmen Ejogo and Kelvin Harrison Jr., respectively) and the family they have welcomed, reluctantly, into their sterile, fortified refuge. The second family also features three people: Will (Christopher Abbott), his wife (Riley Keough) and their son (Griffin Robert Faulkner), all of whom, like their wary hosts, appear to be free, so far, from whatever has ravaged the rest of the world.

But these two camps know little about each other, and the disease, which any of the visitors might have brought into the house unwittingly, kills rapidly and without warning. True to its title, much of the film takes place at night, when doubt, fear, nightmares and paranoia can be their most corrosive.

Two of the characters — Paul’s teenage son, Travis, and Sarah, Will’s sexy young wife — suffer from insomnia. One of their scenes together crackles with a sexual tension that takes on new dimensions of danger, as the method of the disease’s transmission is unclear.

Edgerton’s Paul has already shown himself to be impulsive to a fault, setting up a situation in which mistrust metastasizes into something much worse. For much of its brisk running time, It Comes at Night teeters between delicious atmosphere and almost unbearable tension.

That may not be enough for viewers who have come to expect a payoff accompanied by screaming and bloodshed in a film set in remote locations. There’s plenty of mayhem at the climax. But the “it” that materializes out of the movie’s shadows may not be what you have been led to fear, even though it will be instantly, chillingly recognizable.