German village Igelheims backward priest hopes his sons to succeed him after education in the cathedral school of bishop, but the elder succumbs to disease and the youngest lacks any intellectual drive. Traveling teacher Aesculapius arranges for the inquisitive daughter Johanna to be enrolled too, against wishes of their father. Unfit for the boys-only dorm, she gets to stay with count Gerold, incurring due jealousy of his wife. She has to be dismissed, but survives a Viking pillaging slaughter and assumes brother Johannes';s identity to join a monastery, where she becomes a trainee of the infirmary. Fleeing exposure as female, she arrives in Rome. As a protégée of rivals in the viper nest-like papal court, she ends up elected as pope, but carries count Gerolds baby, guaranteeing exposure.