At its best, the 2015 Poltergeist is a beat-for-beat (but only sometimes shot-for-shot) retread of the 1982 Poltergeist, with Jared Harris substituting for Zelda Rubinstein. And I love Jared Harris, and I'm never sad to see him in a movie, but Zelda Rubinstein was the best part of the original movie. So at its best, Poltergeist '15 is a conspicuously less-good version of a thing that exists in a perfectly fine iteration. At its worst, Poltergeist '15 is basically a disaster site.

I will say this in its defense: it manages to reverse the usual fatal sin of horror movies, particularly ones about ghosts and hauntings, particularly in the modern age. Virtually every such film is at its best when it's simmering along and freaking out the characters, and the minute it starts to explain things and bring in the experts to help exorcise the whatever it is that's causing mischief, everything goes right into the crapper. Poltergeist front-loads all of its worst material, and ends up being kind of interesting as it gets closer to the end, or right about the point that Harris and Jane Adams, in the role of a credulous parapsychology professor at the local university, take over protagonist duties.

That front-loading is dire, though. There's a rule so straightforward, longstanding, and obviously necessary that I'm always baffled when horror filmmakers forget to follow it: start by showing us what normal looks like, so we know what abnormal looks like. Phantasmagorical explosions of style and plotless terror on the European model can get away without laying that groundwork, but none of those words describe Poltergeist at all, which eagerly starts throwing demonic clowns and unseen people in the closet at its central family their very first night in their new haunted house, without even a single evening of vague unease to warm us up. It's not a good way to amp up the tension, it's a good way to blow out the tires on the movie before it's even out of the driveway, and the first half-hour of the film throws out so many creepy images with gothic shadows and a wailing score to tell us that it's time to be scared, it's numbing. It's like director Gil Kenan and screenwriter David Lindsay-Abaire threw the switch from "banal domesticity" to "gaping hellmouth" so hard that they broke it and couldn't switch it back.

Even setting that aside, the first act of the new Poltergeist is amazingly defective. The basic plot is about the same as last time, with the names changed and significantly more emphasis on economic misery: the recently laid-off Eric Bowen (Sam Rockwell) and his writer wife Amy (Rosemarie DeWitt) have settled on a kind of dumpy suburban home as the new place for their family to live and economise as they regroup (Deficiency #1: every character reacts to this house like it's a tumble-down shack that only the most hellishly impoverished would dare to live in, when it's quite a trim, clean 2-story in a nice neighborhood, and if the constant implication that we're in the southwestern Chicago suburbs is meant to be taken seriously, it's certainly setting the grindingly poor Bowens back not less than a couple hundred thousand dollars). And so comes the fateful day when they move in the kids, surly teenager Kendra (Saxon Sharbino) and unbearably adorable moppets Griffin (Kyle Catlett), around 11, and Madison (Kennedi Clements), around five. It's seriously repellent how precious they are; but they have the merit of looking inordinately plausible as DeWitt's biological children.

And so, without further ado, the Bowens are swamped by an army of horrors, most of them plaguing the absurdly high-strung Griffin; eventually, the Whatever It Is in the house seduces Madison into entering her closet, whence she is warped into a hell dimension that, as we'll find out, exactly overlaps the Bowens' house, but only occasionally interacts with it. After which, things settle out into that beat-for-beat retread, and Adams and Harris come along, and it's almost possible to forget just how wretched everything has been so far. Other than Catlett, who's pretty terrific as a preteen neurotic living in the worst imaginable place for a child of his nervous sensibilities. Rockwell and DeWitt are generally terrible in their roles, persuasive as a married couple happy to be with each other as a bulwark against poverty, and nothing else - certainly it's difficult to believe in either of them as a parent, the foundation upon which the entire notion of Poltergeist stands. But it's not sporting to blame the actors for being unable or disinclined to do much with the half-formed characters and situations in Lindsay-Abaire's screenplay, which frequently resembles a skeleton for a script to be built up later more than a coherent movie in its own right. Like the way it treats the Bowens' financial difficulties, which is the central point of some scenes and totally forgotten in others. Or its utter failure to figure out what makes Kendra interesting and necessary as a character in any way.

Kenan's directorial debut came in the form of the motion-capture haunted house adventure Monster House in 2006, and it's easy to see that as an argument in favor of his qualifications for making a family-friendly scary movie (though the new Poltergeist is considerably less interested in being for kids and parents than the original), but none of his facility with genre mechanics shows up here. The first act is one-note and blandly assembled, typified by its pile-up of jump scares of escalating ridiculousness - a scary clown? No, a whole fucking box of scary clowns! No, a freaked-out squirrel jumping at the characters! No, a squirrel with blood red zombie eyes! - and its artless reimagining of moments from the original with absolutely none of its creativity, most prominently a scene that re-creates the wonderful moment in the the first film where the camera pans away from a kitchen only to find that a few moments later every object within it has been stacked into a complicated tower (in the remake, it's a house made out of comic books). Not only is the tone different - in the original it was more mysterious and wonderful than scary, but since the remake is humping "scary" as hard as it possibly can from the second scene, there's no room for that here - it's accomplished in a shock cut instead of a single camera movement, or even a simulated single camera movement. The result is something barely shocking, since Kenan telegraphs it too openly, and certainly not creepy.

It sticks the landing, at least, though not without some stupid touches (a Boschian hellscape of writhing CGI corpses is just silly), with Catlett, Harris and Adams all coming to the fore in the last third in ways that tweak the original enough to feel like the new thing has a worthwhile personality of its own. It's never, ever as good as the first movie, which I don't even personally love all that much, but it maneuvers through the formulaic requirements of a haunted house movie crisply enough.

Don't stay for the mid-credits scene, though; it's jokey awful nonsense, and the worst part of the entire movie with its insipid winking. And it immediately undoes all the hard work of the film's last hour in washing out the foul taste of the first 30 minutes.