After directing Amoureux de ma femme (2018), actor Daniel Auteuil thought he would not direct a movie anymore, unless he felt an irrepressible need to tell a story. This happened when his daughter showed him a blog by Maître Mô, a.k.a. Jean-Yves Moyart, a French criminal lawyer who blogged about his cases. The movie adapts one of these cases, transposing the story from the North to the South of France.
To prepare for the movie, Daniel Auteuil and his DP, Jean-François Hensgens, attended a criminal trial with a similar story to the one depicted in the movie. Auteuil was shocked by the lack of facts in the exchanges between the defense and the prosecution. Similarly, he observed that witnesses often didn't see anything tangible, there was no smoking gun, no motive.