When serious medical conditions are misdiagnosed as demonic possession, it can lead to some pretty disastrous consequences—even death. Marie McClellan told me that she was 15 when she first thought a demon was inside her. A blossoming Canadian girl with dyed green hair and an oversized flannel shirt, she was attending rehearsal for an Easter play at her evangelical church in New Brunswick when she began to feel a fear crawling under her skin. As an actor

playing Jesus was being nailed to a cross with fake blood dripping from his hands and face, McClellan started breathing rapidly and violently scratching herself. “I didn’t know what was happening to me, I just knew I had to get out of there,” she told me over the phone, as she reflected on that harrowing night in 1995. Her behavior was so frantic that she was approached by a pastor, who she said pinned her arms to the floor. His touch only caused her more terror—a common sign of demonic possession. READ MORE