An affair to arouse curiosity (8)
I believe the answer is:
intrigue
I believe this clue is a double definition.
'an affair' is the first definition.
(thesaurus)
'arouse curiosity' is the second definition.
(I've seen this before)
'to' is the link.
(Other definitions for intrigue that I've seen before include "A conspiracy or an affair" , "Plot, conspire" , "Secret love affair" , "Underhand scheming" , "Connive" .)