The success of the series encouraged Adams to adapt it into a novel, which was based on the first four Fits and released in the second week of October 1979. While the second radio series was being recorded in 1979, Adams was commissioned to deliver a pilot script for a television adaptation, which, after a number of delays, was delivered by 1981. The storyline set out by the initial radio series has since appeared in numerous formats including a 1984 video game and a 2005 feature film.