New cast for a show (4)
I believe the answer is:
cats
'a show' is the definition.
(I've seen this before)
'new cast' is the wordplay.
'new' indicates anagramming the letters.
'cast' with letters rearranged gives 'CATS'.
'for' is the link.
(Other definitions for cats that I've seen before include "Musical (felines?)" , "Musical; animals" , "Show" , "Feline mammals" , "Carnivores - stage musical" .)