Storyteller raced back to river, following artist (8)
I believe the answer is:
narrator
'storyteller' is the definition.
(synonyms)
'raced back to river following artist' is the wordplay.
'raced' becomes 'ran' ('run' can be a synonym of 'race').
'back' says the letters should be written in reverse.
'river' becomes 'r'.
'following' means one lot of letters go next to another.
'artist' becomes 'ra' (Royal Academician, member of Royal Academy of Arts).
'ran' written backwards gives 'nar'.
'to'+'r'='tor'
'tor' after 'ra' is 'rator'.
'nar'+'rator'='NARRATOR'
(Other definitions for narrator that I've seen before include "reporter" , "The one who tells the story" , "The person telling the story" , "he gives an account" , "The one telling the story - arrant or what?" .)