A nurse, Alma (Bibi Andersson), has been assigned to care for a famous actress, Elizabeth (Liv Ullman), who suddenly stopped speaking during a performance of Electra and has remained silent ever since. When they go to stay in a seaside house owned by Alma's psychiatrist colleague, the apparently self-confident nurse gradually reveals more and more of herself in the face of Elizabeth's silence. Bergman's extraordinary film explores ideas of projection, the way identity is formed and maintained, thin and disposable as celluloid.