The streaming TV players are leaning hard on Halloween this year, with Hulu launching its monthly horror franchise “Into the Dark” Oct. 5 and Netflix’s “The Chilling Adventures of Sabrina” coming Oct. 26. While “Sabrina” comes pre-sold to its potential audience, tied in as it is to the “Riverdale” universe both through its source material and its creator, Roberto Aguirre-Sacasa, Netflix’s other horror series this October has fewer hooks to grab its audience, and announces its ambitions slowly.

“The Haunting of Hill House,” coming to the streamer Oct. 12, is a horror series that doesn’t immediately make a case for itself; like the best of the genre, it’s slowly insinuating, building in power as it tells a story of repressed trauma and family discord. It’s an effective scare-fest that is at its best when the tale does more than jolt the viewer.

The story is told through flashbacks from an ongoing present in which the five Crane siblings all are dealing with sadness and qualms that have been with them since childhood; we see, in retrospect, the permanently marking time they spent as children living in the eerie Gothic manor Hill House. (In past tellings of this story, including the original 1959 novel by Shirley Jackson, we see only the haunting itself but not its extended aftermath.) Viewers may well be frustrated, at first, by the pace at which connections within the family reveal themselves. Each of the first four episodes tells the story of an individual sibling over the course of a full hour. the first episode, focused on Michiel Huisman’s memoirist Steven Crane, is admittedly genuinely slow going, and his story doesn’t come into focus until later. His siblings, all of whom are more interesting characters, resent Steven’s capitalizing on their family’s history by selling a book, and one about their family’s buried anguish to boot.

But those siblings — Elizabeth Reaser as a dutiful type-A mortician, Kate Siegel as a tough social worker burdened with extraordinary sensitivity, Oliver Jackson-Cohen as a winsome addict, and Victoria Pedretti as the sharpest recollector of family memory — bring a variety of experience into the show, and make it gleam with anguish and with rage. The manner in which complicated ties of loyalty and enmity come into our line of vision as we meet more of the family makes for a viewing experience that rewards attention and delivers painful insight. The episode lengths may be indulgent, but the storytelling within the episodes is sharp, effective, and fairly unadorned. By the time the four surviving siblings come together to mourn the death of the fifth of their cohort, in a bravura fifth episode that claims, and very nearly earns, a 70-minute running time, the show is probing, with acute realism and meaningful texture, what it means to be part of a family and to what one owes to those who survived the same experience.

This all adds up to a show that is less like horror than something else — indeed, the degree to which siblings airing their past and present frustrations with one another forms the plot of this “Haunting” makes it feel a bit like a spin on “This Is Us,” had the Pearsons grown up in a haunted house rather than Pittsburgh. But the show does an elegant job of weaving creeping dread into each character’s past through the presence of their mother (Carla Gugino), a woman seen only in flashback and alternately as warm and protective or coldly demanding and governed by mercurial moods. And, to be clear, there are scares, ones building in intensity and imagination as the show runs on. Writer/director Mike Flanagan, whose previous work includes the Stephen King adaptation “Gerald’s Game,” uses his camera effectively, in one scene showing Reaser, in the deep background, reacting in horror to something in her funeral home and then moving the camera slowly towards her as her siblings rush to join her; in an era of flashy and cheap jump scares, there’s something satisfying to the build of dread that comes when we know we’ll only see the horror when the rest of the characters do.

The most effective scare, though, may be something more elemental: The Crane siblings came through something together that they might not have been able to do solo — and then they split apart, leaving the first of their number to die to do so uncared-for and alone in her consuming memories. With brutal effectiveness, “The Haunting at Hill House” will fill viewers’ hearts with dread, not at the ghosts and apparitions that do, indeed, play a role, but at the wages of time and of pain that’d be easier shared but that’s impossible to talk about. The clever idea to widen the aperture of a horror tale — to tell the story after the haunting seems to have ceased — has given viewers a very special show, one that knows the scariest hauntings are not by ghosts but by memories.

Drama. Netflix (10 episodes, six reviewed), Fri., Oct. 12.

Executive Producers: Meredith Averill, Mike Flanagan, Justin Falvey, Darryl Frank, Trevor Macy.

Cast: Michiel Huisman, Carla Gugino, Timothy Hutton, Elizabeth Reaser, Oliver Jackson-Cohen, Henry Thomas, Kate Siegel, Victoria Pedretti, Lulu Wilson, Mckenna Grace, Paxton Singleton, Violet McGraw, Julian Hilliard.