He has a moving part to play in the theatre (5-7)
I believe the answer is:
scene-shifter
'he has a moving part to play in the theatre' is the definition.
The answer is a person as well as being a singular noun. This is suggested by the definition.
'he has a moving part' is the wordplay.
I cannot quite see how this works, but
'he' could be 'hi' and 'hi' is located in the answer.
'part' could be 'scene' (I have seen 'Part of play ' mean 'scene' so perhaps 'part' could also mean 'scene') and 'scene' is present in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Another definition for scene-shifter that I've seen is " Stagehand".)