16-year-old Maria is forced into Serra D'Aires convent, secretly run by Satanists.

Susan Hemingway
as Maria Rosalea Coutinho

Ana Zanatti
as Mother Alma, the Grand Priestess

William Berger
as Father Vicente

Herbert Fux
as Satan

Vítor Mendes
as António Fernando Queiroz de Melo

Anton Diffring
as Old Priest

Aida Vargas
as Joanna, a Nun

Esther Studer
as Josefina

Dagmar Bürger
as Nun

Herman José
as Manuel Gonçalves