Article pains hopeless actor (8)
I believe the answer is:
'actor' is the definition.
(I know that actor can be written as thespian)
'article pains hopeless' is the wordplay.
'article' becomes 'the' (the definite article).
'hopeless' is an anagram indicator.
'pains' is an anagram of 'spian'.
(Other definitions for thespian that I've seen before include "Tragic actor" , "He paints (anag)" , "Player" , "Dramatic actor" , "stage performer" .)