Film actress about to enter gala event (6)
I believe the answer is:
bacall
'film actress' is the definition.
I know nothing about this answer so I can't tell whether this works.
'about to enter gala event' is the wordplay.
'about' becomes 'ca' (abbreviation for 'circa').
'to enter' is an insertion indicator.
'gala event' becomes 'ball' (I've seen this in another clue).
'ca' put inside 'ball' is 'BACALL'.
Can you help me to learn more?
(Other definitions for bacall that I've seen before include "Lauren -, The Big Sleep actress" , "Lauren --, US actress" .)