The first 20 minutes of Hogir Hirori’s extraordinary documentary has the beat of a gripping thriller, full of hushed voices, car chases, and the terrifying sounds of gunfight. Much of it shot at night, the film follows Mahmud, a member of an organisation called the Yazidi Home Center (YHC), and his trips with other volunteers to the dangerous al-Hawl camp in Syria which holds people with Isis links. The group’s goal is to retrieve and rescue Yazidi women who were kidnapped and sex-trafficked by Isis. Termed “sabaya” by their captors, the women endured unimaginable abuse, leaving them with debilitating lifelong trauma.

Intertwining with these tense, heartbreaking moments is the mundane daily life at Mahmud’s house, which doubles as a temporary shelter for the women. Recurring moments of his mother making food or his young son playing about the courtyard act as a calming balm to the victims’ psychological hurt, a semblance of the normality that hopefully awaits them in their home town in Sinjar. Sabaya is also especially poignant in how it doesn’t see Mahmud as a heroic figure. There’s a moving matter-of-factness to his routine of checking the continuous messages from people seeking their loved ones or his calm confrontation with Isis sympathisers who hide the Yazidi women in the camp.

Equally astonishing is the bravery of former sabayas who return to the camp as infiltrators for YHC. Just like Mahmud, they too share a staggeringly unruffled resilience, considering the danger of their tasks and the ordeal they have suffered. At one point, the group calmly discuss whether to fetch their weapon from a car as bullets are flying nearby. This is all complemented by Hirori’s unvarnished handheld cinematography that does not sensationalise the women’s plight; instead it respectfully and sombrely makes tangible their harrowing experience.

• Sabaya is released on 20 August in cinemas.