What leads us to accept a particular belief, credo or fact? What's the difference between conviction, groupthink and madness? And when should we start asking questions? This issue of Granta looks at cults, faiths and ideologies, and asks how they turn us into followers. Miriam Toews on shunning, pacifism and her youth in a strict Mennonite community; Matilda Gustavsson on teenage Christian groups, faith healing and speaking in tongues; Lauren Baldwin on growing up with the Children of God; Andrea Stuart on the feminist porn industry; Shalom Auslander on Orthodox Judaism; and Roberto Saviano on hiding out from the Italian mafia - along with new writing from Tim Adams, Lauren Baldwin, Emma Cline, Sam Lipsyte, Gwendoline Riley, Aatish Taseer, Adam Thorpe and many more.