A young girl enters a Catholic convent at the time when its mother superior is struggling to come to terms with the radical reforms of the Second Vatican Council in Maggie Betts’s “Novitiate.” Though it takes a few melodramatic shortcuts, the film is a generally shrewd, thoughtful portrait of life in a cloistered Catholic community at a moment of radical change in the Church.

We are introduced to Cathleen Harris in 1954, when she is seven (and played at that age by Eliza Mason). Her parents Nora (Julianne Nicholson) and Chuck (Chris Zylka) are at each other’s throats over his drinking, and they quickly split up. Though an agnostic herself, Nora believes that Cathleen should be introduced to religion so that she can eventually make up her own mind, so she takes the girl to church. Five years later, Cathleen (now played by Sasha Mason), is offered a scholarship at a newly-opened Catholic School run by nuns from a nearby convent of the Sisters of the Blessed Rose, and there she is taken under the wing of the supportive Sister Margaret (Ashley Bell). By age seventeen, now played by Margaret Qualley, Cathleen has become convinced that she has a vocation and announces, to Nora’s distress, that she intends to enter the convent as a postulant or candidate. If she is not required to leave for some reason, she will enter the novitiate, living under strict rules, including silence, to test whether she is among those who will be permitted to take final vows.

In 1964 the convent—a large one with a substantial community—is governed by the imperious Reverend Mother Marie St. Clair (Melissa Leo), a firm traditionalist with a fear of the changes being mandated by the council—and, it will become apparent, an authoritarian temperament that can sometimes explode into cruelty toward her charges. Sister Mary Grace (Dianna Agron), who is apparently the novice master, represents a more gentle, supportive stance, but she abruptly leaves the order for unspecified reasons.

The film follows Cathleen and her fellow novices through their period of testing. Some, like Sister Sissy (Maddie Hasson) are moved by a genuine calling, like her. Others, like Sister Evelyn (Morgan Saylor), have entered the order as the result of family pressure, while another amusingly cites the beauty of Audrey Hepburn in Fred Zinnemann’s 1959 “The Nun’s Story” as inspiring her decision. Sister Emily (Liana Liberato), on the other hand, is the epitome of old-school rigidity, and from her brusque manner a Marie St. Claire in the making. Then there is Sister Emanuel (Rebecca Dayan), a transfer from another, apparently more liberal, convent, whom the others are suspicious of at first; but she and Cathleen will eventually develop a relationship with erotic overtones that will raise the specter of what used to be referred to as a “particular friendship.” Nonetheless she will ultimately reach the stage of final profession, when she will take solemn vows to God and the community. It is at this point, with her dubious mother watching from a pew, that she will either make a lifelong commitment—or not.

This is of course Cathleen’s story, and Betts treats the young woman’s soulfulness with respect, noting her doubts and uncertainties but never dismissing her honest commitment. Qualley plays her with nuance. It’s almost inevitable, however, that attention should often gravitate to the Mother Superior, whom Leo plays with relish. At times she can come across at a monster—the fashion in which she deals with the novices during interrogation sessions can turn brutal. And one scene set in the refectory is disturbingly out of place. But Betts does not omit to show her more vulnerable side, particularly in a conversation with progressive Archbishop McCarthy (Denis O’Hare), who prods her to implement the reforms of the council in her4 community. Even if you agree with the changes he’s insisting on—like giving up self-flagellation as a means of correction—you might register the pain the woman feels in surrendering the sole area of female dominion in the church to male authority. The remainder of the cast all do admirable jobs, with Nicholson standing out as Cathleen’s concerned mother.

On the technical side the picture is outstanding, with smooth cinematography by Kat Westergaard and equally expert editing by Susan E. Morse. Also notable is the background score by Christopher Stark, which incorporates music from a variety of contemporary composers.

The look of the film benefits from its location, a former nunnery in Nashville. One absolutely accurate aspect of “Novitiate” is a final caption that informs us that after the changes Mother Superior so dreaded implementing, great numbers of nuns left their convents and new recruits were few. To see the result, you might check out Sobo Swobodnik’s extraordinary 2015 documentary “Silentium,” about the handful of ageing Benedictine sisters remaining in a huge medieval German convent. In a way it’s a perfect complement to “Novitiate.”