For its initial hour or so, Never Rarely Sometimes Always provides an interesting enough, vérité-style trip through one particularly complex teenage abortion.

Elevating writer/director Eliza Hittman’s vastly superior follow-up to her Moonlight knockoff Beach Rats is a brave central performance by newcomer Sidney Flanigan as 17-year-old Autumn, who decides to terminate her unwanted pregnancy.

Thanks to unflinching, practically unspoken support from her cousin Skylar (Talia Ryder), whose immediate, reflex-like springing to action is borderline tearjerking, Never Rarely Sometimes Always soon becomes a story of true sisterhood as the young women boldly travel by bus from their rural Pennsylvania hometown to New York City — the nearest place where Autumn can get the procedure done.

Hittman films her protagonists in an aptly straightforward, typical low-budget manner, and keeps their dialogue sparse, allowing facial expressions and simple gestures to convey the growing tension of their mission, producing something akin to a less stylized, female-centric My Own Private Idaho.

When new information does arise, it’s primarily through medical professionals that Autumn encounters in her unexpectedly complicated odyssey, the peril of which is compounded by a dwindling cash supply, steps required for her mom (a credible Sharon Van Etten) not to find out, and a time crunch. Likewise making things more difficult than necessary is Autumn's pride and her frustrating unwillingness to accept what she deems to be too much help, even from people who genuinely want to make her life better and have no ulterior motives.

During one such critical encounter — a harrowing, largely unbroken exchange that rivals the processing sequence from The Master — the significance of the film’s title is revealed while Autumn is broken down by a rare sustained stretch of self-reflection and genuine care from an adult. In this Scene of the Year candidate, her surprising personal history comes spilling out, adding unforeseen gravitas to the trip, and turns a good, promising film into a nearly great one.

The exchange additionally stresses the extent to which Autumn and Skylar are overmatched for their journey, and subsequent scenes sharply depict the fear and excitement of being in NYC without a safety net, turning Never Rarely Sometimes Always into a solid New York film in the process.

The non-humorous sibling of the recent Saint Frances, the also film valiantly shows some of the same unglamorous and rarely-seen details of abortions at a time when women’s rights are under attack arguably more than ever.

On top of these already staggering obstacles and realistic suspense from a wholly believable set-up and execution, there’s the troubling sense that Autumn and Skylar are never quite in the clear — nor will they ever be — and that their circumstances are far more prevalent than most people would like to admit.

The feeling of ongoing danger extending beyond the film’s hopeful final shot is a significant dramatic achievement and solidifies Never Rarely Sometimes Always as a must-see.

Grade: A-minus. Rated PG-13. Now available to rent via Amazon Prime Video, iTunes, and other participating on-demand services.

(Photo: Focus Features)