New cast play parts (4)
I believe the answer is:
acts
'play parts' is the definition.
(I've seen this in another clue)
'new cast' is the wordplay.
'new' indicates an anagram.
'cast' with letters rearranged gives 'ACTS'.
(Other definitions for acts that I've seen before include "Legal documents" , "Deeds; book of the Bible" , "religious work" , "Pretends" , "NT book; laws" .)