Sophie, a quiet and shy maid working for an upper-class French family, finds a friend in the energetic and uncompromising postmaster Jeanne, who encourages her to stand up against her bourgeois employers.

Mika, heiress to a Swiss chocolate company, is married to celebrated pianist André and stepmother to his son, Guillaume, whose mother died in a car wreck on his tenth birthday. Their lives are interrupted by the unexpected arrival of Jeanne, a young woman who has learned she was almost switched with Guillaume at birth.