In 1973, six years before she was found dead in her car – the result of a "probable suicide", according to a Paris coroner – Truffaut tried to cast her in his paean to the movies, Day for Night; for reasons that remain a mystery, he couldn't get in contact with her. He was certainly smitten by what he saw in Bonjour Tristesse. He wrote in 1958: "When [Seberg] is on screen you can't look at anything else. Her every movement is graceful, each glance is precise. The shape of her head, her silhouette, her walk, everything is perfect; this kind of sex appeal hasn't been seen on the screen."
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...she has an anxious halo that bespeaks a reservoir of tremendous instability barely held in check: the specter of drug problems, emotional difficulties, dangerous liaisons. [Nathalie] Richard brings a fascinating bifurcated quality to this woman, impish yet cynical and almost terrifyingly vulnerable once you get past her seen-it-all facade: in her fierce not-quite androgyny, she seems to bring other scarred worlds to bear on the movie, to anchor its lightness in underground passions, perils, ambiguity. She isn't quite like anyone else in the movie, or the movies themselves -- Richard's so much quicker than a Jean Seberg or Anna Karina, as if channeling Martina Navratilova's reflexes through memories of the heroines of half a dozen Big Star songs. -- Howard Hampton. "The Strange Case of Irma Vep." In Olivier Assayas, ed. Kent Jones (Wien: SYNEMA, 2012), 108.