Scenery fills empty theatre: one with wings (6)
I believe the answer is:
tsetse
'one with wings' is the definition.
'scenery fills empty theatre' is the wordplay.
'scenery' becomes 'sets'.
'fills' is an insertion indicator.
'empty' means to remove the middle letters.
'theatre' with its centre taken out is 'te'.
'sets' inserted inside 'te' is 'TSETSE'.
(Other definitions for tsetse that I've seen before include "Disease-carrying fly" , "Bloodsucking African fly" , "source of sleeping sickness" , "African transmitter" , "fly across Africa" .)