Some actors opening trunk (5)
I believe the answer is:
torso
'trunk' is the definition.
(both can mean a person's chest)
'some actors opening' is the wordplay.
'some' says the answer is hidden in the clue (some of the parts of the word are used).
'TORSO' is hidden in the letters of 'actors opening'.
(Other definitions for torso that I've seen before include "Main part of human body" , "Chest" , "Body's trunk" , "Roost on trunk?" , "part of body will be found" .)