Clémence Poésy was born Clémence Guichard in Paris in 1982. She took her mother's maiden name, Poésy, as her stage name. She attended an alternative school for most of her education, but spent her last year at L'École alsacienne. She trained at the "Conservatoire National Supérieur d'Art Dramatique", with her first roles being for French TV series between 1997 and 1999, Un homme en colère (1997) and Les monos (1999). Her first feature film was a German production, Olgas Sommer (2002), in 2002 and her second the 2003 French production, Welcome to the Roses (2003).
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