People having fits of apoplexy was a very common plot device in classic literature. Today, it’s more commonly known as a stroke, which just doesn’t sound as romantic.
Thanks to the Who Shot J.R.? mystery that concluded the 1981 spring season of Dallas and launched the 1981 fall season, the cliffhanger quickly became a plot device in many primetime television shows and was not limited to the genre.
Mature Sci-Fi now can treat other sentient races not as sole plot device but as additional characters.
Soon there wasn't a supernatural stone left unturned, as Dark Shadows became a compendium of every myth, legend and plot device.