Celebrity currently featuring in musical, not finished (6)
I believe the answer is:
renown
'celebrity' is the definition.
(synonyms)
'currently featuring in musical not finished' is the wordplay.
'currently' becomes 'now' (I've seen this in other clues).
'featuring in' indicates putting letters inside.
'musical' becomes 'rent' (Rent is an example).
'not finished' means to remove the last letter.
'rent' with its final letter removed is 'ren'.
'now' placed within 'ren' is 'RENOWN'.
(Other definitions for renown that I've seen before include "Plane's maximum width" , "High repute" , "Good reputation" , "Fame and public acclamation" , "Fame, respect" .)