“Cellar Door” is an attempt at the thriller-as-parable, a suspenseful story about a troubled couple tested by temptation and the ugly “answers” they might find by peeking behind that which they’ve been warned to never open, the cellar door of the film’s title.

Set up as horror, with a tepid script entirely too content to “explain” and over-explain itself in only the least satisfying ways, it never amounts to much more than a 97 minute tease.

Jordana Brewster and Scott Speedman play Sera and John, Pacific northwesterners struggling to have a baby. He’s an architect, she’s a college professor of statistics. And logic?

Their latest failed IVF has them abandon their swank city apartment for the suburbs. But they’re on a budget, and nothing in this place where “we can live the life of our dreams” is within their price range.

That’s why their real estate agent sends them to visit the mysterious and wealthy Emmett (Laurence Fishburne). He is charmed, and they are charmed by him. And next thing you know, he’s offering them his mansion. Like Sera, he associates a place with unhappy memories.

The offer has but one catch. “You must never open the cellar door.” Multimillion dollar house, ours for the asking? For free? Sure, we can do that.

But can they?

The story suggests that all isn’t happy in these lives and this marriage. Complications intervene, and next thing you know, each becomes half-obsessed with finding out what’s in that cellar. Because that’s better than facing the problems (Addison Timlin is set up as “the other woman”) right in front of their faces.

Director Vaughn Stein — “Terminal” and “Inheritance” were his — and his team get the look and tone right, a somber tale told in the grim greys of the coming (Portland) winter. But the entire enterprise feels like a cheat, a movie with no real payoff, no big jolts and no surprises in all this “explaining” in the third act.

We don’t need a new character waltzing in late and using the phrase “Faustian bargain” if the script isn’t delivering that.

The third act twists are undercut by such nonsense. The suspense doesn’t build and the flatlining performances don’t hurtle or even meander into any sort of satisfying or logical melding with those “explanations” of what “secrets” can do to a marriage.

Fishburne is serene, with the barest suggestion of sinister. But Speedman and Brewster, whatever their strong suits, can’t make us believe their characters’ panic, quiet fury or rage in a script that can’t stop teasing that it’s something it will never be.

Rating: R, violence, sex, profanity

Cast: Scott Speedman, Jordana Brewster, Addison Timlin and Laurence Fishburne.

Credits: Directed by Vaughn Stein, scripted by Sam Scott and Lori Evans Taylor. A Lionsgate release.

Running time: 1:37