Hope County, Montana. Land of the free and the brave, but also home to a fanatical doomsday cult known as The Church of Eden's Gate that has slowly been infiltrating the residents' daily lives in the past years. Mary May Fairgrave, a local barkeep, has lost almost everything to the Church: her parents died in suspicious conditions and her brother, entranced by the cult leader's charismatic words, has vanished. When the authorities refuse to investigate further, she decides to take matters into her own hands.