The third part of Ingmar Bergman's trilogy of faith (the others are 'Winter Light' in 1961 and 'Through the Glass Lightly' in 1963).
The relationship of two sisters Ester (Ingrid Thulin) and Anna (Gunnel Lindblom) reaches breaking point when they arrive in a strange country and stay in a large hotel, empty but for a troupe of dwarf entertainers.
Ester is suffering from a terminal disease and has become overly protective of Anna and, to escape, Anna goes out to find a man and ends up bringing back a waiter to her room.
This then proceeds to both arouse and anger Ester culminating in a bitter and violent argument between the sisters.