Arnaud Ducret wears a Baume & Mercier Classima

In Monsieur Je-Sais-Tout (2018), released in English as Mr. Know-It-All, Vincent Barteau sits on an exam table while the club doctor inflates a blood-pressure cuff on one arm, and on the other wrist sits a steel watch with a black dial on a black leather strap. The French watch site Montres de Luxe identified it as a steel Baume & Mercier Classima. No second source exists, and the frame gives a clear look at the watch without a readable brand, so the call stands as a single-source identification of a deliberately plain piece.

The film comes from Alain Gillot's 2015 novel La Surface de reparation, and it pairs Arnaud Ducret's Vincent, a 35-year-old football coach standing 1.92 meters, divorced, who broke with his family at sixteen when his father refused to let him play professionally, with his nephew Leo, thirteen years old and 1.53 meters, autistic and an accomplished chess player, played by Max Baissette de Malglaive. Leo lands in his bachelor uncle's life without warning, and the story works toward Vincent earning the boy's trust back out of his mutism, with Alice David's Mathilde, the doctor with the cuff, alongside. Francois Prevot-Leygonie and Stephan Archinard wrote and directed the adaptation, and Ducret prepared for it by watching Rain Man several times, studying how Tom Cruise played opposite Dustin Hoffman.