I've been haunted by a drama I saw in the 70s. I think it was probably a made for tv drama rather than a film. All I remember is that a woman from the present time looks in the mirror and sees herself dressed as a nun. I think the story involved a young nun and a monk who had had an illicit affair. One or possibly both of them may have been bricked up behind a wall as a result. It was set in the present with something happening to trigger ghostly events but it's only really the image of this women looking in the mirror that I can remember.
Not much to go on but does anyone know what this was?