Cat Women of the Moon was a 1950s film that followed a popular motif in science fiction; an all women society surviving without men. Charlotte Perkins Gilman explored the idea as early as 1915 in the classic novel 'Herland'. In part one of a two part programme we look at how science fiction has been used to examine relationships between the sexes - and in some cases, more than two sexes. In many novels the exploration of sexuality is unconventional and experimental. Some societies have more than one sex, in others people can change sex at will. In certain imagined worlds people form relationships with aliens or don't have sex with flesh and blood beings at all - but with artificial life forms instead. The programme includes contributions from some of Britain's leading science fiction writers including Iain Banks, China Mieville and Nicola Griffith. The programme is presented by the writer Sarah Hall, author of 'The Carhullan Army' and 'The Electric Michelangelo' which was short listed for the Booker Prize. The programme is produced in Manchester by Nicola Swords.