<P> A six episode series dubbed the "Hexagonal Phase" was broadcast on BBC Radio 4 beginning on 8 March 2018, exactly 40 years after the first series' initial broadcast in 1978, and concluding 12 April 2018 . The series is based on the sixth novel And Another Thing...by Eoin Colfer and adapted by the director Dirk Maggs who included some dialogue and material based on unfinished ideas in Adams's papers . Dirk Maggs produced the series which features members of the original radio and television casts . </P> <P> The first two series were first released on record (as broadcast radio in 1979), audio cassette (revised from radio) and CD (revised revised) in 1988, marking the tenth anniversary of the first broadcast of the first episode . These were the first programmes of any kind released on CD by the BBC Radio Collection . The two radio series were known simply as "the first series" and "the second series" until 1992 when the BBC made its first re-release in separate boxes as "The Primary Phase" and "The Secondary Phase". The episodes were released with those titles in 1993, and again in 1998, for the series' twentieth anniversary . In 2001, they became the first programmes of any kind re-released by the BBC Radio Collection in an MP3 - CD format . </P> <P> A 3 - CD set of the Tertiary Phase was released in mid-October 2004, before the final episodes were broadcast . These CDs contain extended material, previously cut to make 27 - minute episodes for radio . A 2 - CD set of the Quandary Phase was released at the end of May 2005, and a 2 - CD set of the Quintessential Phase was released at the end of June 2005 . Both sets again include material that was originally cut for reasons of timing . The sixth series is scheduled for release on CD on 13 April 2018 . </P> <P> A script book for the final fourteen episodes was released in July 2005 . The book is entitled The Hitchhiker's Guide to the Galaxy Radio Scripts: The Tertiary, Quandary and Quintessential Phases . Dirk Maggs writes in his introduction that the "book is a companion volume to The Original Radio Scripts ..." </P>

Bbc audio hitchhiker's guide to the galaxy