Seventh Dimension is the BBC's regular radio slot for science fiction, fantasy and horror. It is broadcast on the digital radio station BBC Radio 7 at 2 p.m. (GMT in winter, BST in summer), seven days a week and then repeated each day at 6 p.m. and midnight with host Nick Briggs. Most of the programs are full cast dramatizations and the remainder are book readings. The Seventh Dimension has hosted both standalone stories and serials. Most of the programs are drawn from the BBC's extensive archives and have previously been aired on other BBC stations. A few Seventh Dimension shows are new commissions, such as Undone, The Spaceship and Planet B.
In addition to digital broadcasting in the British Isles, BBC Radio 7 streams live on the internet, and all programmes can be heard up to a week later via the listen again service on the iPlayer.