Director Yasmin Fedda, who is from a Palestinian and Syrian background and lectures in film at Queen Mary University of London, has created a powerful and urgent documentary tribute to those who have been “forcibly disappeared” by the Assad regime in Syria, estimated to be around 150,000 since 2011.

Fedda focuses on two people: dissident writer and computer programmer Bassel Khartabil, who was abducted in October 2015 in Damascus, and Father Paolo Dall’Oglio, the hugely popular and admired Christian priest who was taken in July 2013 in Raqqa. She uses existing video of these two, from various family members and organisations, along with her own footage showing the campaigns of the loved ones left behind with their burden of anguish and their need to battle on and bring these crimes to the world’s attention.

In particular, we talk to Bassel’s wife, Noura Ghazi, and Paolo’s sister Immacolata, or Machi. Their testimony is deeply moving: they are courageous, stoic, determined. It is heartbreaking to see Noura, so young and joyous in Bassel’s company, then careworn and marooned in a spiritual void of uncertainty about whether Bassel is alive or dead. It is wrenching also when Machi tells us of the choice she has to make: to stop thinking about her brother or to endure the pain of continuing to campaign, to post online, to keep the search alive, but with it the danger of unthinkably raw grief. As she poignantly puts it: “I prefer to take the risk of hoping.”

The forcibly disappeared of Syria emerge from this film as comparable to los desaparecidos of Argentina in the dark days of the junta – a tyranny that was brought low at least partly due to the women who bore public witness to those taken.

• Released on 26 February on True Story.