Nestled deep in the postcard-perfect French Alps, the Grande Chartreuse is considered one of the world’s most ascetic monasteries. In 1984, German filmmaker Philip Gröning wrote to the Carthusian order for permission to make a documentary about them. They said they would get back to him. Sixteen years later, they were ready. Gröning, sans crew or artificial lighting, lived in the monks’ quarters for six months--filming their daily prayers, tasks, rituals and rare outdoor excursions.