Co-operate in theatrical performance with dance (4,4)
I believe the answer is:
play ball
'co-operate' is the definition.
(I've seen this before)
'theatrical performance with dance' is the wordplay.
'theatrical performance' becomes 'play' (I've seen this before).
'with' says to put letters next to each other.
'dance' becomes 'ball' (ball is a kind of dance).
'play'+'ball'='PLAY BALL'
'in' acts as a link.
(Other definitions for play ball that I've seen before include "Agree to comply with someone else's rules" , "Do what is needed" , "go along" , "meet a delivery?" , "Be cooperative" .)