Ban boobs on queen in big film (11)
I believe the answer is:
blockbuster
'big film' is the definition.
'blockbuster' can be an answer for 'film' (I have seen 'Successful film ' mean 'blockbuster' so perhaps 'film' could also mean 'blockbuster'). I am not sure about the 'big' bit.
'ban boobs on queen' is the wordplay.
'ban' becomes 'block' (both can mean to forbid or prohibit).
'boobs on queen' becomes 'buster' (I can't justify this - if you can you should give a lot more credence to this answer).
'block'+'buster'='BLOCKBUSTER'
'in' acts as a link.
Can you help me to learn more?
(Other definitions for blockbuster that I've seen before include "Commercial success" , "Film or book making huge profits" , "Large and forceful film, person etc" , "Hugely successful film or book?" , "best seller?" .)