A longer reflection on Under The Skin (Jonathan Glazer, 2013) is here: http://kubrickontheguillotine.com/2014/06/18/on-sound-and-silence-in-jonathan-glazers-under-the-skin/
At a crucial point in the alien’s uncomfortable warmth towards humanity, Scarlett Johannson is people-watching. She does a lot of people-watching, observing and learning about human movement and interaction. In one of these sequences, the faces of people become overlayed with each other, washed with an orange light, in a sequence reminiscent of F. W. Murnau’s Sunrise: A Song of Two Humans (1927). It is a beautiful trick of lighting and digital manipulation. There is a similarity in subject here, too, a sort of visceral experience of a life that is unknown, experienced through the eyes and body of an onscreen vessel. It is part of the alien’s journey to discovering human impulse, observing a way of life and movement that she is unfamiliar with—like that of the bright city lights to a rural commoner—and she becomes drawn to it.