Marie-Castille Mention-Schaar began her career in cinema as a producer for Vendredi film, a company she co-created with Pierre Kubel and Frédéric Bourboulon. Together, they produced numerous films in the early 2000s including films by Antoine de Caunes (Monsieur N and Désaccord Parfait) and Pierre Jolivet (Zim and co, Je crois que je l’aime). She wrote the screenplay for La Première étoile (presented at FFC 2010) and directed her first feature film three years later, amusingly entitled Ma Premiere fois (My First Time). Her second film, Bowling, inspired by a news story regarding a demonstration to stop the closing of the maternity ward in a hospital in Carhaix, resonates with Once in a Lifetime (Les Héritiers), which she presented at FFC 2015.
Marie-Castille Mention-Schaar presented her 2016 film, Heaven Will Wait (Le Ciel attendra) at FFC 2017.