Based on the medieval legend of Pope Joan, who was made Pope for a brief period around 855 A.D. The movie presents her existence as fact, though it is questionable that Pope Joan really did exist, and portrays her relationships with other notables of the time.

Liv Ullmann
as Pope Joan

Olivia de Havilland
as Mother Superior

Jeremy Kemp
as Joan's Father

Franco Nero
as Louis

Maximilian Schell
as Adrian

Lesley-Anne Down
as Cecilia

Trevor Howard
as Pope Leo

Keir Dullea
as Dr. Stevens

Natasa Nicolescu
as Joan's Mother

Sharon Winter
as Joan as a Child