Does the unauthorised use of material mean there’s a plot? (10)
I believe the answer is:
conspiracy
'there's a plot?' is the definition.
(conspiracy is a kind of plot)
'does the unauthorised use of' is the wordplay.
'does' becomes 'cons' (both can mean to commit fraud).
'the unauthorised use of' becomes 'piracy' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'cons'+'piracy'='CONSPIRACY'
'material mean' acts as a link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for conspiracy that I've seen before include "Joint action undertaken secretly" , "This is intriguing" , "scheme" , "Plot" , "that involves plotting" .)