This is an excerpt from a 1954 film which is set in London and is also known as 'Knave Of Hearts'. Joan Greenwood plays Norah and Gérard Philipe plays André Ripois. The director is René Clément.
She did speak French, but I really think she is dubbed here. I just checked, she speak French with her own voice in Jean Boyer's Garou-Garou, le Passe-Muraille, 1950.
