“Ida” is a story of faith and identity, an exquisite, austere drama in a plaintive minor key.

The film is set in 1962, a turning point in Polish history. The nation is relaxing from hard-core Stalinist authority into a society where people listen to jazz and experiment with new personal freedoms. Yet the convent where the film begins looks unchanged from the Middle Ages.

At the center of the story is Anna (played by newcomer Agata Trzebuchowska), who arrived among the nuns as an orphan. Now a young novitiate, she leaves the convent for the first time as she weighs whether to take her vows or enter the secular world. Her Aunt Wanda, a judge, reluctantly takes her in and together they literally uncover the secrets of their family’s wartime past.

So who is the title character, Ida? The answer comes as a major surprise. It throws into question whether Anna is free to choose her future or is still bound by a destiny set in motion before she was born.

The film is above all the drama of two women on a journey of self-discovery. Naïve Anna is a perfect foil for her hard-living aunt (Agata Kulesza). The older woman followed her own set of orthodoxies. Years before, she was a public prosecutor so bloodthirsty and partisan she was called Red Wanda.

As the days of show trials recede and personal liberties expand, she has outlived her usefulness. She’s still enough of a provocateur to push hard against Anna’s faith. When the girl discovers her aunt drunk, in the arms of a stranger, Wanda sarcastically invokes Mary Magdalene, declaring, “This Jesus of yours loved people like me.” The film ponders how strongly our beliefs can be challenged before they crack.

“Ida” softens its harsh truths with a look of timeless beauty. The images have the milky, caressing glow of Dutch paintings. Shooting in black and white, with a static camera and minimal editing, director Pawel Pawlikowski re-creates the threadbare feel of Poland’s Communist winter. The boxy film frame adds an aura of confinement. Yet each drab environment is captured in soft light and elegant compositions.

We are asked to decide if Wanda appeared to tempt Anna to damnation, or the niece arrived to rescue the aunt. Wanda tests the would-be nun’s spiritual strength, taunting her that giving up worldly pleasures isn’t much of a sacrifice “if you haven’t tried it.”

On her last night before deciding whether to return to the convent, the 18-year-old honors her aunt’s challenge. She puts on a pretty dress, slugs vodka and goes to a dance club, wobbling in her aunt’s high heels. She couples up with a handsome musician to the dreamlike sounds of jazz icon John Coltrane.

It’s an odd declaration of love for her difficult relative, and a huge step for a girl who never imagined having a family outside her religious order. Quietly commanding and serene, “Ida” is understatement and intelligence employed to terrific effect.