The occurrence in childhood of falling asleep or being made to go to bed at a critical moment in a TV show or movie, resulting in never finding out how the plot is resolved. It often haunts one up through adulthood.
From the _Batman: the Animated Series_ episode, "Beware the Grey Ghost," in which Batman recalls how, as a young boy, he fell asleep halfway through an episode of the Grey Ghost TV series. He must now track down the episode and watch the ending in order to solve a series of crimes.
I've never seen the end of Dune. I kept getting Grey Ghosted whenever it was on TV.
Remember the _Eerie, Indiana_ with the tupperware? My mom Grey Ghosted me right at the halfway point, so I never found out if they escaped.