Out of the Unknown is a British television science fiction and horror anthology drama series, produced by the BBC and broadcast on BBC2 in four series between 1965 and 1971.

Most episodes of the first three series were dramatisations of science fiction short stories. Some were written directly for the series, but most were adaptations of published stories. The first three series were exclusively science fiction, but that genre was mostly abandoned in the final year in favour of horror-fantasy stories, with only one story based around science-fiction.

Many videotapes of episodes were wiped in the early 1970s, as was standard procedure at the time. A large number of episodes are still missing, although some have resurfaced: for example, "Level Seven", an episode in series two originally broadcast on 27 October 1966, was returned to the BBC from the archives of a European broadcaster in January 2006.