Searching through your archives it seems that no one has brought up PBS's famous MYSTERY! program. My parents were huge fans and every Sunday night at 8 I distinctly remember running into my room and slamming the door shut as soon as I heard the strains of the opening theme and the EDWARD GOREY illustrated opening credits flashing across the television screen.
I adore MYSTERY! now, but when I was little there was nothing more terrifying than Sherlock Holmes, Miss Marple, or Poirot solving brutal murders. One episode in particular of THE RETURN OF SHERLOCK HOLMES starring the fabulous JEREMY BRETT remains seared into my mind after all these years. The episode is entitled "Devil's Foot" and the mystery involves three people, a sister, who had apparently been literally scared to death, and her two brothers who had been driven mad by whatever had killed the sister.
When Holmes is notified of the deaths it flashes to a shot of the siblings sitting around a table in the living room, just as they had been the night before, but this time the women is slumped over to one side, clearly dead, her hands frozen into place around her neck and her eyes almost completely rolled back into her head. One of the brothers is rocking back and forth in a chair muttering to himself and the other is grabbing his head while white foam comes pouring out of his mouth.
This episode aired the one night I chose to watch with my parents after they had been raving about how good the series was and how much I would like it. Needless to say that when I saw this little tableau on the screen I calmly got up, walked to my room, and didn't watch MYSTERY! again until I was at least 17 or 18. To this day that scene still creeps me out.
Thanks, SIR ARTHUR CONAN DOYLE!
Sadly, I am unable to find any images of the scenes I've described from this particular episode. It is on YouTube though! The scene takes place right at the beginning of this segment: