Storyteller's stirring rant and roar (8)
I believe the answer is:
narrator
'storyteller's' is the definition.
('narrator' can be a synonym of 'storyteller')
'stirring rant and roar' is the wordplay.
'stirring' indicates an anagram.
'and' says to put letters next to each other (I've seen this in other clues).
'rant' put after 'roar' is 'roarrant'.
'roarrant' with letters rearranged gives 'NARRATOR'.
(Other definitions for narrator that I've seen before include "Anecdotist" , "The one who tells the story" , "One who tells the tale" , "Storyteller" , "Someone who tells a story" .)