In 2014, more than 5,000 Yazidis were captured and enslaved by ISIS forces that swept through the Sinjar region in northern Iraq. Most of the men were slaughtered, while the women were kidnapped as spoils of war and traded as sex slaves. More than 3,000 remain in the hands of ISIS. Following the largest mass kidnap of women and girls this century, it's time for revenge and Stacey Dooley (Meet The Young Americans, Sex In Strange Places) is on a mission to know more. As ISIS lost ground last year, around 2,000 Yazidis managed to escape or were freed. Among them were a group of young women who have formed an all-female fighting unit to hunt and kill the ISIS militants who kidnapped, raped and enslaved them. Of the 127 strong battalion, a number of the girls were themselves enslaved by ISIS. This daring documentary takes the viewer to the heart of their training ground - and ultimately to the frontline - where these women are engaged in the fight against ISIS. Jihadi's dread facing female fighters because they believe if they are killed by a woman they will not make it to Jannah, the heavenly afterlife. With extraordinary access, Stacey Dooley takes us deep into one of the most terrifying stories of modern times, through the eyes of the world's most unexpected fighting force.