“Soul Mates” is a “Saw” styled torture-then-kill thriller that hangs on an online dating hook and the cackling menace of Mr. Blond Bad Guy Neal McDonough.

A tale of obvious twists and traps and under-reacting performances, about the best one can say about it is that there’s an underlit gloom to the production design that lets McDonough’s sequined-tux turn as “The Matchmaker” pop out.

Allison (Annie Ilonzeh of TV’s “Arrow” and “Person of Interest”) wakes up shackled to Jason (Charlie Weber of TV’s “How to Get Away with Murder”) in a dungeonesque bedroom, neither of them knowing who the other is.

Someone “jumped” them and put them there together. Someone has pictures, phone recordings and video of their lives, knows all their associations, past lovers. Someone is playing “a game” with them, someone whose ads are scored to the ear-worm “Getting to Know You” from “The King and I.”

They ponder their fate but never “work the problem” as they’re led from one room to another, facing touch screen commands and horrific dilemmas that begin promisingly enough.

They’re quizzed “about” each other, which is a way of “getting to know you,” albeit it under duress. And they’re forced to sing karoake to save a gagged and tied stranger dangling over a big meat grinder.

Allison struggles through Jason’s beloved “In the Air Tonight” (Phil Collins). Jason has no prayer of pulling off Allison’s “How to Love” (not a Lil Wayne fan, I guess).

Strangers, loved ones and people from their past turn up as victims they must try to save. A shock collar is among the instruments of torture introduced as they’re lectured about what it’s going to take for The Matchmaker “to make an honest man and woman out of you” “before the walls of loneliness close in on you.”

Cue the walls, closing in like a “Star Wars” trash compactor.

Binge eating and showers and having sex to save themselves all hurl at this hapless duo, who can’t excuse their numbed reactions to all this trauma with “shock.” Leading lady and leading man have got to give us more than this.

The script, like the villain, is pitiless and the pawns in the “game” not remotely interesting enough to invest in.

And just when you think it can’t fail any further, they “explain” what we figured out two acts ago. And explain it some more.

McDonough is always a good bad guy for the money. But not very suspenseful or scary, and somewhat soulless, that’s the bottom line on “Soul Mates.”

Rating: R, violence, sex, nudity, profanity

Cast: Annie Ilonzeh, Charlie Weber and Neal McDonough.

Credits: Directed by Mark Gantt, scripted by Chris LaMont and Joe Russo. A Faith Media release.

Running time: 1:26