A timeless story supported by song and dance connoisseur (10)
I believe the answer is:
aficionado
'connoisseur' is the definition.
(thesaurus)
'a timeless story supported by song and dance' is the wordplay.
'timeless story' becomes 'fici' (I can't justify this - if you can you should give a lot more credence to this answer).
'supported by' becomes 'on'.
'song and dance' becomes 'ado' (I've seen this in other clues).
'a'+'fici'+'on'+'ado'='AFICIONADO'
(Other definitions for aficionado that I've seen before include "ardent follower" , "Admirer" , "freak" , "Fan (Sp.)" , "supporter" .)