Winged sandals in unfinished story and song (7)
I believe the answer is:
talaria
'winged sandals' is the definition.
(I've seen this before)
'unfinished story and song' is the wordplay.
'unfinished' means to remove the last letter.
'story' becomes 'tale' (synonyms).
'and' means one lot of letters go next to another.
'song' becomes 'aria' (piece of music in an opera).
'tale' with its last letter taken away is 'tal'.
'tal'+'aria'='TALARIA'
'in' acts as a link.
(Other definitions for talaria that I've seen before include "Winged sandals of Mercury" , "Winged sandals of Hermes" .)