The Little Brothers and Sisters want to practise their faith "in the midst of life, among the people", following Charles de Foucauld, the monk who lived among the Tuaregs of southern Algeria at the beginning of the 20th century and was shot there in the turmoil of the Tuareg rebellion against the French colonial power. A missionary who wanted to convert by example and "in secret", not by word, "like Jesus in Nazareth". In the Hoggar Mountains of southern Algeria, Foucauld built a hermitage at 2700 m above sea level, to this day a place of spiritual retreat. It was also Foucauld who documented the language, everyday life and troubadour culture of the Tuaregs. The film describes the life of Foucauld as well as that of the Christian brotherhood, which today lives in close proximity to the Muslim Tuaregs.