“She Rides Shotgun” is a gripping A-list B-movie, a morally ambigious and illogically logical thriller for our amoral, illogical times.

Based on a novel by Ben Harper, Nick Rowland’s film grabs a solid, time-proven scenario — a child, on the lam and in jeopardy with a dangerous man — and decorates it with showdowns, chases, who-can-you-trust quandaries, to-the-death brawls and shootouts.

In cinema shorthand, it’s a less gonzo “The Professional,” just as moving as “Gloria” and as troubling as a “A Perfect World.”

A nine-year old waits for her ride after school in wintry New Mexico. Her mom is late. Very late. And she’s damned wary of that guy who rolls up in a beater and shouts “You come over here. I just need to talk to you.”

It turns out, that guy is Nathan, her dad (Taron Egerton, pitch-perfect). “Everything’s fine,” he assures her. But he “just got out.” And little Polly (Ana Sophia Heger) isn’t taking anything he says at face value.

She picks up on clues. Her dad is wearing her stepdad’s jacket. The safety glass of the driver’s side window is shattered and sprinkled all over the car

“What have you done to Mom?”

“I haven’t done ANYTHING!”

As we suspect, that’s not entirely true. As they hit the highway, ditch the beater and duck into a cash-only motel, Polly gets her answers. Her parents are dead. There’s a manhunt for her dad.

But as Dad makes frantic calls to one “friend” after another with “I gotta get gone” desperation, we and Polly pick up on the truth. Dad did something that caused the “double homicide” on the TV news, but he didn’t do it himself.

That “A” in a circle tattooed on his neck he got in prison? That’s the Aryan Steel gang. Nathan did something to cross them, and now he’s got a “green light” on him and everyone he holds dear. His advice is blunt and dire, even if it doesn’t go much beyond how to defend yourself with a baseball bat.

“You gotta feel week to get strong…If they’ve hurt people, cracking their heads is not a sin.”

Rob Yang of TV’s “Succession” and “American Rust” plays a police detective on the hunt who figures out this “green light” business early on. How might that tie into the region’s meth wars, the sprawling meth lab they call “Slabtown” and the “God of Slabtown” who runs it?

Egerton is wound up tight as Nathan, but young Miss Heger (“Things Heard & Scene,” TV’s “Life in Pieces”) has to bounce from shocked and sad to confused and distracted to wholly engaged in their enterprise and what must be done to get away, if indeed “getting away” is her best destiny. She’s quite good in the part and makes a scripted character arc that could give you whiplash at least somewhat plausible.

I mean, the kid’s just lost her mother. It should take more than a few hours to get over that.

The many hands in the screenplay serve up a sea of dirty sheriff’s deputies and filthy police with the rare “good” apple, flinty banter about “peckerwood” white supremacist gangs that lord it over law enforcement (David Lyons and the always formidable John Carroll Lynch play cops) and a finale that is cliched mayhem.

It isn’t “The Professional,” Rowland (“Calm with Horses”) isn’t Luc Besson — his pacing’s slack, for starters — and Heger probably won’t turn out to be the next Natalie Portman.

But she’s pretty good and “She Rides Shotgun” is a compelling, gripping B-movie ride, a picture that reaches for highfalutin “Trojan Horse” allegories when what it does best is a lot more obvious. It puts a child we instantly empathize with in jeopardy, and makes us wonder if gangs, cops or her dad are the biggest threat to her well-being.

Rating: R

Cast: Taron Egerton, Ana Sophia Heger, Rob Yang, Odessa A’zion, David Lyons and John Carroll Lynch

Credits: Directed by Nick Rowland, scripted by Jordan Harper, Ben Collins, Luke Piotrowski and Nick Rowland, based on a novel by Harper. A Lionsgate release.

Running time: 2:00