Look at lead actor with disapproving expression during children's entertainment (8)
I believe the answer is:
peekaboo
'disapproving expression during children's entertainment' is the definition.
I can't tell whether this defines the answer.
'look at lead actor' is the wordplay.
'look' becomes 'peek' (peek can mean to look at quickly).
'at' means one lot of letters go next to another.
'lead actor' becomes 'aboo' (I can't explain this - if you can you should give a lot more credence to this answer).
'peek'+'aboo'='PEEKABOO'
'with' is the link.
Can you help me to learn more?
(Other definitions for peekaboo that I've seen before include "Infants' hiding-and reappearing game" , "Game played with young children" , "minor revelations" , "Game played with a young child" , "Peering-through-fingers game" .)