You couldn’t ask for a more appropriate introduction to Caylynn, the youngest daughter in “Jacinta,” than to see her with her mother of the title pinning her down. It’s all in fun, a few weeks after Jacinta’s been released from prison — the 26-year-old every bit as wily as her 10-year-old child during their first time together in years, but after they wrestle playfully, things turn serious when Jacinta teaches her how to raise her fists just right. It becomes obvious as Jessica Earnshaw’s utterly engrossing debut wears on, that the instinct to teach Caylynn self-defense isn’t misguided, but Jacinta isn’t likely the best person to educate her when so much of her young life has been consumed with protecting herself from her mother, already managing her hopes when it comes to seeing her so sporadically and somewhat conscious of her insidious addiction to drugs when living a state away from Jacinta with her grandparents.

There are far worse things to be aware of as a child, as Earnshaw illuminates brilliantly in the longitudinal doc that takes stock of his one generation can pass its pain onto the next, starting most improbably at a correctional facility in Maine where Jacinta is incarcerated with her mother Rosemary. The scene would be extraordinary under any circumstances as Jacinta tempts fate by attempting to talk to Rosemary from the prison yard while her mother is in a cell up above, looking outdoors after being previously punished by guards for doing so, showing the strength of their bond, but as the film gradually reveals with great care, it’s been a greater source of torment than comfort when Rosemary came from a family well-known in Portland for gun, drugs and burglary and passed what she learned of the family trade to her daughter. The incredible nature of these early moments almost makes you overlook the fact that Earnshaw has remarkable access to both the prison and her subjects to film, which only deepens in intensity when Jacinta is released and allows the filmmaker to follow her through enrollment in a sober house and eventually back into the wild of Lewiston, a former mill town where there’s little else but drugs to pass the time and ease desperation.

Jacinta’s commitment to a warts-and-all depiction is admirably unflinching, honored by Earnshaw’s own dedication to put in the time and temperament to show how treacherous her path is, always there to capture small moments that tell you everything over the years the film covers and resisting intervening at moments when you pray that she would when relapse appears inevitable, knowing it would deny the truth of the situation of how inescapable addiction is. Earnshaw and editor George O’Donnell meticulously structure the film to show how despite how totally drugs have taken control of Jacinta, they are a mere extension of forces that are less obviously pernicious, introducing the people in her life at just the right moment to shed light on how thoroughly she was failed at every turn in her upbringing. From a mother whose ideas about showing approval stem from all the wrong things to the absence of any social net beyond prison to prevent her from falling further, it is both insightful and torturous to watch relatives such as Jacinta’s father Rick or sister-in-law Billie speak with such clarity about the heartache they feel for her with the tacit acknowledgement that they’re no longer in any position to do anything about it.

Still, “Jacinta” isn’t without hope, finding its subject attempting to break a cycle, not for herself, but for Caylynn, who may be best off if she never sees again, and while it may chronicle a downward spiral, the film is buoyed by elucidating the sacrifices Jacinta makes after already enduring so much, knowing the damage it could cause to her daughter’s future. Even if Earnshaw’s cinematography wasn’t often stunning, her ability to visualize how the harshest confinement doesn’t require bars makes the film a must-see.

“Jacinta” will be available to stream through DOC NYC from November 11th through 19th. A full schedule of upcoming screenings will be here.