Personnel screen English Oscar star (4)
I believe the answer is:
hero
'star' is the definition.
(I've seen this before)
'personnel screen english oscar' is the wordplay.
I cannot really see how this works, but
'english' could be 'e' (abbreviation) and 'e' is found within the answer.
'personnel' could be 'hr' (Human Resources) and 'hr' is present in the leftover letters.
'oscar' could be 'o' (phonetic alphabet: alpha, bravo, charlie etc.) and 'o' is present in the answer.
This accounts for all the letters.
This may be the basis of clue (or it may be nonsense).
(Other definitions for hero that I've seen before include "Chief male character in story or film - probably very brave" , "Principal character in a film or novel" , "Brave guy" , "Courageous man" , "Man of valour" .)