THE ADVENTISTS explores the realities, and some of the ironies, of one of the few American-born religions: Seventh-day Adventism. Historical re-enactments offer a glimpse into the church’s beginnings, including its defining moment: the mid-19th century event known as the Great Disappointment. Several decades later, Dr. John Harvey Kellogg built a breakfast-food empire and pioneered a new kind of healthcare facility based on Adventist principles of a healthy lifestyle: a plant-based diet; regular exercise; the avoidance of alcohol, tobacco or illegal drugs, and a holistic focus on education and community life.