In “Cats”, perhaps, or in another show you may see them (6)
I believe the answer is:
actors
'another show you may see them' is the definition.
I can't tell whether this defines the answer.
'in cats perhaps or' is the wordplay.
'in' is an insertion indicator.
'cats perhaps' becomes 'acts' (cat is a kind of act).
'acts' enclosing 'or' is 'ACTORS'.
'in' is the link.
Can you help me to learn more?
(Other definitions for actors that I've seen before include "They 23 down" , "The Gleeson boys, say" , "Luvvies" , "Players on stage" , "Cast" .)