The lone woman on a team investigating an instantly-notorious and very public murder finds herself understanding and even envying the murderess in “In Her Place,” a thriller with a message about the lot of women in 1950s South America, and the world.

Chile’s submission for the Best International Feature Oscar is based on a true story about a shooting in a swank hotel where Chile’s aristocracy gathered, a case that made headlines as a novelist faced prison for killing her lover, seemingly mimicking a more famous crime years before.

Elisa Zulueta plays Mercedes, a secretary to the judge (Marcial Tagle) charged with investigating this case and passing judgement. Mercedes is a wife and mother and the engine that makes that judge’s office run, a smart cookie in a patriarchal time in a very sexist culture.

Every man who calls her “Mechita” and “Mecha,” from her piggishly traditional husband (Pablo Macaya) to Judge Veloso is diminishing her and her status with a mere nickname. She must wait for the judge to leave his “club” before giving him his messages. “No women or salemen allowed.”

She keeps their cluttered, down-market apartment together and finishes each day by doing all the cooking while her failing portrait photographer spouse can’t be bothered to lift a finger, and her older teenage sons couldn’t imagine themselves pitching in.

The son who refers to her as “judge,” as if recognizing her career talents and importance, aspires to go to law school, become a lawyer and then a judge. But even he laughs when his sibling cackles “Mom could be your secretary (in Spanish, or dubbed into English).”

Something about this “crime of passion” that the judge seems inclined to minimize gets under Mercedes’ skin. She knows her boss has a “type,” rich, pretty women who do little time for their crimes. But she sees this case resembling one from years before.

She’s seen the suspect, Maria Carolina Geel (Francisca Lewin), her face covered in blood, led out of Santiago’s Hotel Crillón. She’s taken notes on every interrogation the judge conducts about the case, learning why that face was so bloody that the press has taken to nicknaming her “The Vampire.”

And whatever the judge and his aide Domingo (Gabriel Urzúa) think, whatever counter-arguments the persistent defense attorney (Pablo Schwarz) makes, in or out of the judge’s chambers, Mercedes sees clues that point to the “art” of it all.

Geel insists on going by her pen name and not her legal one, which might point to a dissassociative personality disorder that the male doctors who conduct her psychological evaluation could flag in her defense. The various witnesses, relatives and friends of the deceased paint a dark portrait.

The suspect treats the one other woman in all this, Mercedes, as a natural ally, but not one of the same class with the same privileges. Mercedes is the one sent to fetch Geel clothes and toiletries, to be delivered to her cushy incarceration in a convent. And in the suspect’s posh apartment, Mercedes tries on her lipstick, dabs on her perfume, and allows herself to sample this life of wealth, quiet contemplation and art.

Two-time Oscar-nominee (for best documentary) director Maite Alberdi immerses us in this world and underscores the sexism of that era, and even the patronizing benefits of it. No mere woman accused of such a “crime of passion” could possibly face the severest penalties. Especially a member of the elite.

Zulueta’s performance is a subtle transformation, from a functionary taken for granted by literally every man in her life to someone more made-up, better-dressed and more confident in the world thanks to her access to all the trappings in Geel’s apartment and the comfort of her life.

We feel little pity for the husband who apparerntly isn’t even as good a photographer as Mercedes. He’s using her inherited cameras to take these bridal photos, and can’t get the exposure time or the lighting right without her gentle manipulations.

Her “manipulations” of the judge are just as overt.

But much in this drama is left unsaid, so it’s up to Zulueta (“El fantasma”) to let us see what she’s feeling and thinking with just her eyes. She does.

It’s a terrific piece of work, and she and Alberdi and fellow screenwriters Inés Bortagaray and Paloma Salas have created in Mercedes a grand fictional conceit. This is a woman in man’s world who “gets it” and through her, we see this case as the prism it was, breaking down Chilean and Latin American society and sexism and illuminating a whole gender being ignored, past the moment a heinous crime was committed and into the “justice” that might be delivered by the men who ran that world, or thought they did.

Rating: PG-13, violence

Cast: Elisa Zulueta, Francisca Lewin, Marcial Tagle and Pablo Macaya

Credits:Directed by Maite Alberdi, scripted by Inés Bortagaray, Paloma Salas and Maite Alberdi, based on a book by Alia Trabucco Zerán. A Netflix Release.

Running time: 1:30