Androids — robots that look like humans — serve as central characters in movies and television all the way back to the origins of those forms. In movies, they primarily have two values: they are mostly symbols of technological threat — the dangers of industrialism, in earlier movies, and the dangers of human ingenuity and automated slave labour in later ones — or they are, less often, symbols of how we contemplate the meaning of "human", the issues connected with "personhood". Androids depicted in television shows have a more varied symbolic value, mainly because the writers have the time and need to develop various plotlines. So, in a television series, the signification of the android can vary depending upon the episode we view.