80's Horror: Man Zips Down Forehead to Reveal Brain

by Anonymous

I have a vague memory of watching an American film in the 80's set in modern times but then switching back to the Confederate era.

It involved a married couple in a big plantation home and when the husband (I think his character was a doctor) turns evil he laughs manically, unzips his forehead, rips off his scalp and exposes his brain, while trying to kill his wife.

I think the title had the word 'insane' or 'insanity' in it, or something with the word 'evil'.

I hope someone can help with this as it's driving me potty - I also think this might have been a cornball horror-type film.