Watching Alex Pettyfer play scenes in which he’s in psychotherapy in his directing debut, “Back Roads,” the temptation is overwhelming to put the actor himself on the couch.

With this film and his previous one, “The Strange Ones,” a dark, brooding same-sex “Lolita,” Pettyfer isn’t just reaching for the sexually daring and darker-than-dark. He’s torching his heart-throb image and making one question just what he sees in these roles, what makes him want to get these movies made, which his presence in the credit ensures.

“Back Roads” is a turgid Red State Gothic mystery melodrama — without meth, without Southern accents. Working poor lives are depicted in grim degrees of hopelessness, and an entire family bears the brutal burdens of abuse, disruption and abandonment.

Like “The Strange Ones,” it fascinates, repels and at times bores as the pot boils and the plot roils. At least Pettyfer and screenwriter Tawni O’Dell (adapting her novel) manage to hide their twists and deliver the occasional almost-shocking surprise.

“Back Roads” is framed within an interrogation. Harley Altmyer (Pettyfer) is  interrogated by the sheriff (Robert Patrick). “Why did you kill her?”

It’s the pre-cell-phone mid-’90s, and in the film’s one, long flashback, we see the miserable life that put Harley in that spot.

He’s a young man, barely out of his teens, wearing the weight of the world in his eyes and on his shoulders. He’s the guardian of three sisters, their sole provider. Teen sister Amber (Nicola Peltz of TV’s “Bates Motel”) has “started dating.”

“Define dating,” Harley acidly observes. She’s gone bottle blonde, dropping her Daisy Dukes for any boy who might rescue her from her home situation.

Younger teen Misty (Chiara Aurelia) is old enough to know what’s going on and on the verge of open rebellion herself. Only eight year old Jody (Hala Finley) seems savable, the only kid there with a prayer of a normal life.

Why? Mom’s in prison for killing Dad. And Dad abused them.

Harley meets the county social services therapist (June Carryl) in between shifts at the local supermarket. Every minute is a struggle, with Amber in a constant “You’re not the boss of me” rage, the house falling down around him and bills piling up.

He quakes at his burdens and glowers at his mother (Juliette Lewis, letting us see a woman in despairing collapse) as she tries to comfort Jody during a prison visit, and comes to a conclusion.

“You WANT to be here!”

He’s starting to wonder about what happened “back then,” beginning to piece it together. And that’s just another weight piled upon his shoulders.

Something about his vulnerability appeals to the neighbor mom Callie (Jennifer Morrison of “How I Met Your Mother”) to a little girl Jody plays with. She chats with him at the supermarket, reaches out to him when he comes to pick up her sister.

They share an interest in the impressionists and a grinding loneliness and hunger. Married or not, she wants him and in the worst, animalistic and brutish way.

The movie’s melodramatic flourishes are many — one overwrought, contrived and extreme situation after another dropped into the stew until it all boils over.

The heat of Callie and Harley’s sexual congress is matched by the fury only two siblings can unleash on each other, Amber’s teen tantrums about what Harley isn’t able to do — provide for them, get her a car. She’s moving on and never looking back, she declares.

“You’ll be living down the road in a trailer, with five kids and no husband,” he spits back.

In the opening scene the sheriff talked about Harley’s rifle, and we see him and most everybody in his family show they know how to use it. That just adds to the dread.

“Back Roads” goes too far and on for too long as sick twist after sick twist shows up until you long for the “normal” of Mama June and Honey Boo Boo. What they were going for is a “Tobacco Road,” a sexualized/sensationalized riff on “Winter’s Bone” — no meth, just abuse, its ripple effects and the differing ways children respond to it.

As a director, Pettyfer shows little style. No, underlighting many of your scenes isn’t inspired. As an actor, he’s mastered brooding and seething and breaking down but nothing lighter.

Peltz makes a fine white trash fury and Lewis has aged into someone perfect for broken matriarch roles like this.

But whatever it wants to say about abuse, its mental, social and sexual impact on its victims, however “daring” it aims to be, “Back Roads” loses in its pursuit of the sordid.

And let’s hope Pettyfer, who has a supporting role in Steven Soderbergh’s “Panama Papers” thriller, “The Laundromat,” has gotten “sick and pervy” out of his system — at least for now.

MPAA Rating: unrated, explicit sex, descriptions of violence and abuse

Cast: Alex Pettyfer, Jennifer Morrison, Nicola Peltz, Robert Patrick, Juliette Lewis

Credits: Directed by Alex Pettyfer, script by Tawni O’Dell, based on her novel. A Samuel Goldwyn release.

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