A former member of the female comedy trio "Les Filles" with Michèle Bernier and Isabelle de Botton, Mathy is best known for her starring role in the long-running Josephine, Guardian Angel television series.

[3] In the early 1980s she performed in a number of theatre roles and appeared in Le Petit Théâtre de Bouvard television show.

She formed a touring comedy troupe "Le Trio des Filles" (The Three Girls) which performed shows such as Existe en trois tailles (Available in Three Sizes) from 1988 to 1993.

[3] In 1993 she performed in the TV movie Une nounou pas comme les autres (A Nanny Like No Other), which garnered a 52.7% market share (~12 million viewers) in France.

Mathy first met restaurateur Benoist Gérard when she picked him out of the audience, as part of one of her stage comedy routines.