The story unfolds in 1899, deep in the Hautes-Alpes region. Soudain is a hamlet encircled by snow on the high plateaus of a remote mountain. One stormy night, its inhabitants witness the arrival of Aimée, a young, secular and republican primary school teacher who is due to stay for the winter to teach a handful of children. But shortly after her arrival, an avalanche swallows up its first highlander…