Joachim von Hartmann was born and raised in Buenos Aires by his loving German mother, Liese, along with his identical twin. But when Joachim moves to Paris with Liese in his late teens, his twin enters a dark world and refuses to leave his beloved Argentina. Joachim begins training to be a butler, fascinated by the meticulous precision and intense demands it involves, and goes on to work in some of the grandest homes in England.
Olivia White has given ten years of her life to her magazine, which failed, taking all of her dreams with it. A bequest from her mother allows her a year in Paris to reinvent herself. She needs help setting up a home in a charming Parisian apartment. It is then that her and Joachim's paths cross.
Joachim, on a whim, takes a job working for Olivia for a few weeks, which turn to months as the unlikely pair discover they enjoy working side by side. At the same time, Joachim is shocked to learn the family history he never knew, involving his grandfather's sinister wartime activity, and also to hear news of the dangerous criminal his twin has become. While Olivia struggles to put her life back together, Joachim's falls apart.