Life in the city wasn’t working for them, so the Hayes family pulled up stakes and moved to “the mountain.”

Here, there’s no “job” for mom or dad, no bus ride to school for their two daughters.

“We make the rules, now,” is Dad’s explanation and their creed.

Sister Mary is young enough to roll with it all. But tweenage Riley is taking this all in, accepting that they’re “pioneers” until she starts to understand what she doesn’t understand, acting out until she figures it out.

“Manifest West” is an engrossing, surprisingly serious portrait of a family in crisis. Whatever the Hayes clan hoped to get from abandoning the city, going “off the grid,” depending on themselves and their fellow grid-shedding neighbors, Riley, played by Lexy Kolker in a breakout performance, could be the one who figures it all out.

This wasn’t a conscious, measured choice. It was a Hail Mary pass, a move made out of desperation. Whatever self-sufficient dreams Dad — played by Milo Gibson in perhaps his best performance yet — had, he’s brought them there because he didn’t know what else to do.

Mom (Annet Mahendru of “The Walking Dead”) isn’t well. And whatever everybody else brought into the woods with them, that isn’t changing her condition or the strength of the single thread holding this family together.

Co-writers/directors Joe Dietsch and Louie Gibson gave us the “Most Dangerous Game” variation “Happy Hunting,” and graduate from the primal and visceral to something subtler and more sophisticated with this thriller with a hint of “Leave No Trace” about it.

The Hayes find themselves in a community of supposed like-thinkers. But Riley sees what we see — free range kids lashing out at this lifestyle, attitudes towards guns and authority that range from adult to infantile — and a world that tests the worthy and prepared, and the medicated, cityfied, unschooled and stressed equally.

Movies with a mental illness subtext always have a glib grasp of their malady, but our writer-director team keep that in the background, minimizing this common shortcoming.

Milo Gibson, brother of co-director Louie — both of them sons of Oscar-winner Mel Gibson — shows us the fears of a man out of his element, struggling to keep it together but increasingly frazzled and paranoid about his role as family provider and protector.

Mahendru manages a subtle enough version of wife Alice’s mental struggles. Michael Cudlitz plays a neighbor who reminds us that not everyone who uses firearms is a nut, and allows us to underestimate him with a performance of sober depth.

But young Kolker, of TV’s “Shooter” and “Agents of S.H.I.E.L.D” is our guide into the psyche of a tween trying to turn into a teen amongst the other kids in this world. Riley makes her own mistakes, flunks her own tests, comes to her own conclusions and might very well have her own mental issues thanks to the consequences of her family’s move, her father’s actions and her own response to them. And Kolker lets us see it all, and read just what is sinking in, what her next wrong move might be with us worried for her all along the way.

Rating: unrated, violence, teen drinking, profanity

Cast: Milo Gibson, Lexy Kolker, Annet Mahendru and Michael Cudlitz

Credits: Scripted and directed by Joe Dietsch and Louie Gibson A Samuel Goldwyn release.

Running time: 1:31