If horror movies are meals, “The Darkness” is one that takes the smorgasbord approach.

It’s got demons, a haunted house, portals to “the Third World,” a demon-targeted autistic kid, Native American rituals, an alcoholic mother who sees things but whom no one will believe, and a Mexican American exorcist.

The “Darkness” effects — shadows and ghost handprints and underworld storms projected onto a suburban bedroom ceiling — are decent.

Kevin Bacon and horror vet Radha Mitchell (“Silent Hill”) anchor a solid cast. Director Greg Mclean did the primal Aussie horror pic “Wolf Creek” and its sequel.

But it’s a lumbering affair, a fright-fest with no frights, a scary movie with zero sense of urgency.

A family vacation into the desert parks of the American southwest puts their tweenage autistic son, Mikey (David Mazouz) in touch with Native American spirits, thanks to his stumbling into a ritual religious cave. He puts some engraved stones into the backpack he never lets out of his Autism-focused sight.

And when they get home, all Native American hell breaks loose.

Only it doesn’t. This patchwork script meanders and dawdles. The neighbor’s canine barks an insistent warning.

“What is UP with that dog?”

And Mikey communes with the spirits, letting them and their menacing ceremonial masks and sooty footprints into Mom’s nice, clean house.

Too much time is spent establishing this family’s dysfunction. Mom used to drink, daughter (Lucy Fry) has rage and eating issues, architect Dad acts awfully guilty about…something.

It takes a good hour for anybody to catch on, and even longer to seek any sort of help. Of course, their first call is to a supernaturalist.

The frights have not punch to them and the slow pace — see Radha Mitchell in the tub, see Radha swim laps — is the result of a film stuffed with filler scenes that don’t advance either the plot or us to the edge of our seats.

The scariest thing about “The Darkness” turns out to be the trailers to this summer’s more promising horror offerings, “Lights Out” and “Don’t Breathe.”

MPAA Rating:PG-13 for thematic elements, some disturbing violence, brief sensuality and language

Cast: Kevin Bacon, Radha Mitchell, Lucy Fry, Paul Reiser
Credits: Directed by Greg Mclean, script by Shayne Armstrong, Shane Krause, Greg Mclean.

Running time: 1:32. A High Top/BH Tilt release.