Star Trek: TOS – Dagger of the Mind (S01E09)
A plastic dome hangs from the ceiling of a treatment room, a small light turning inside it. That is the entire neural neutraliser, the device the whole episode is built around, and on paper it is nothing. A prop the art department could have thrown together in an afternoon. By the closing minutes it is one of the most frightening objects the original series ever put on screen, and the distance between the first impression and the last is most of what makes “Dagger of the Mind” worth talking about.