NOVA explores the past, present, and future of American television including the potential of cable, the Columbus, Ohio, two-way TV experiment, the array of new techniques and their potential social impact. Will the new video technology let people see what they really want, rather than what the networks want?

As plague sweeps 17th century England, the Doctor discovers a more exotic threat at work - shipwrecked Terileptil convicts, intent on making the planet their own.