Handsome young man making fuss about wrongdoing (6)
I believe the answer is:
adonis
'handsome young man' is the definition.
(I've seen this before)
'fuss about wrongdoing' is the wordplay.
'fuss' becomes 'ado' (synonyms).
'about' is a reversal indicator.
'wrongdoing' becomes 'sin' (sin is a kind of wrongdoing).
'sin' back-to-front is 'nis'.
'ado'+'nis'='ADONIS'
'making' acts as a link.
(Other definitions for adonis that I've seen before include "Most 8 Greek youth" , "Extremely handsome young man" , "Greek idol" , "Aphrodite's love" , "dish" .)