Andrea Hoffman's latest book The Girl Who Beat Isis, based on a series of interviews with a young Yazidi woman she met in an Iraqi refugee camp.
Andrea is calling her 'Farida Khalaf', who escaped from months of captivity at the hands of Islamic State after being sold as a sex slave, subjected to mental and physical torture and rape, and passed around by human traffickers.
Farida's remarkable story is one of survival and eventual escape, as well as the bitter experience of what comes after.
Lynne Freeman talks to Andrea Hoffman about this harrowing story.