Works Wagner wrote occasion bold action (7-2)
I believe the answer is:
derring-do
'bold action' is the definition.
(I've seen this before)
'works wagner wrote occasion' is the wordplay.
I cannot quite understand how this works, but
'occasion' could be 'do' (do is a kind of occasion) and 'do' is found in the answer.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for derring-do that I've seen before include "Literary word for heroic courage or action" , "Courageous action" , "'bold action'" , "Brave and heroic feat(s)" , "Daring deeds" .)