Paul Naschy as Father Adrian Dunning

Maria Perschy as Patricia Gibson

María Kosty as Deborah Gibson

Mercedes Molina as Leila Gibson

Joan Llaneras as John Gibson

Luis Induni as Udo

Jordi Torras as Dr. Lewton Buchanan

Roger Leveder as Richard Harrington

Marta Avilés as Sandra

Juan Velilla as Comisario

Florencio Calpe as Christian

Dora Santacreu as Abigail

Esteban Dalmases as Policía (uncredited)

Jack Taylor as Father Adrian Dunning (voice)