A Promise (2014)
Directed by Patrice Leconte

Film Synopsis

Germany, 1912. Friederich, a young graduate of modest means, is engaged as the private secretary to an ageing business magnate, Karl Hoffmeister. As his health takes a turn for the worse, Hoffmeister invites Friederich to his house, where the latter soon finds himself drawn to his employer's young wife Charlotte. Friederich makes every effort to keep his amorous yearnings to himself, unaware that Charlotte harbours similar feelings for him. When the separation comes it is sudden and brutal. Hoffmeister sends Friederich to Mexico to oversee an iron mining operation. Charlotte's shock reaction to this news makes Friederich aware that she has fallen in love with him. But it seems to be a love that can have no future. As war breaks out, Charlotte wonders if she will ever see Friederich again...