Actor Postlethwaite (4)
I believe the answer is:
pete
'actor postlethwaite' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for pete that I've seen before include "- Seeger, US folk singer" , "filmed with his 1 across [DRAGON]" , "For his sake" , "Small 14 [PETER JONES]" , "- Doherty, Babyshambles singer" .)