Even though she had escaped with the man she loved, she was not free: Her family members still considered her married to the older man based on the earlier agreement. They pursued her and had her and her new husband thrown in jail, accused of adultery, conceiving a child out of wedlock and bigamy.

The striking thing about the video is the success of Ms. Soleimani in persuading Soheila’s family members to cooperate, and drawing out of them their full-throated justification of practices like baad, and the absolute right of men to determine whom their sisters and daughters should marry.

As Soheila watched the video, she came to the part where her father visits her in prison, and plays in an apparently loving and grandfatherly way with her toddler, Mr. Mohammad’s son, who was born after Soheila and Mr. Mohammad were both imprisoned. Soheila burst into tears, and covered her face with her veil, then peeked out again at the image of her father in a moment of seeming kindness.

Ms. Soleimani first found Soheila in prison, but soon afterward Women for Afghan Women took up her case, and she was transferred to the group’s Kabul shelter as they successfully appealed to the Supreme Court to grant her a divorce from her first husband on the grounds that it was the illegal outcome of the abusive custom of baad. While she waited for her husband’s case to be resolved, she asked to return to her family.

She said her father told her that he would accept her home on one condition: “Kill your son.”

As the video continues, Ms. Soleimani interviews both the father and the half brother, Aminullah, whose own long-ago elopement was the offense that led to the bartering of Soheila’s life.

Her father, who lives by traditions that have often been overtaken by laws, at least once seems confused by the goings-on in Kabul, saying for instance that the government keeps Soheila in the shelter and would not let her return to him, even though the government does not run the shelter.

When Soheila saw Aminullah and her father sitting together, explaining themselves in the documentary, she pushed the screen aside and said, “I won’t watch them, I hate them both.”