Undine (Paula Beer) works in Berlin as a historian and guide to the city‘s development. She has a small apartment at Alexanderplatz, a master‘s degree in history, and a freelance contract. But underneath the appearance of her modern city life lurks an old myth: if the man Undine loves betrays her, she has to k...

Two actresses, Béatrice Dalle and Charlotte Gainsbourg, are on a film set telling stories about witches - but that's not all. 'Lux Æterna' is also an essay on cinema, the love of film, and on-set hysterics.