What old media would be the most terrifying if rebooted?

I am not against reboots or remakes as a concept. The TV show version of Buffy was actually a reboot. A lot of good fanfic is a remake on some level, especially the AU/fusion trend. That said, some concepts would not work in the hands of today's film makers and show runners. Some concepts would not fly with today's fannish spaces. Some concepts only work within the the context of the era they are from.

What show (or movie or whatevers) would you be most horrifyied to see a reboot announcement for?