The story is set in an alternate America where witches ended their persecution 300 years ago by cutting a deal with the U.S. government to fight for their country. In the present day, three young women receive basic training in combat magic at a base called Fort Salem. The series follows them from basic training into early deployment. In this world, the traditional roles of gender and power are flipped. Women are on the front lines fighting looming terrorist threats that are familiar to our world, but their tactics and weapons are supernatural.