It will eventually happen that an act gets banned (4,3)
I believe the answer is:
turn out
'it will eventually happen' is the definition.
The definition suggests a singular noun but the answer is not.
'an act gets banned' is the wordplay.
'an act' becomes 'turn' (turn is a kind of act).
'gets' says to put letters next to each other.
'banned' becomes 'out'.
'turn'+'out'='TURN-OUT'
'that' is the link.
Can you help me to learn more?
(Other definitions for turn out that I've seen before include "parade" , "Eject" , "End up" , "Prove" , "All the voters" .)