Insured in secret (10)
I believe the answer is:
undercover
This clue could be a double definition.
'insured' is the first definition.
Both the answer and definition are adjectives. Maybe you can see a link between them that I don't see?
'in secret' is the second definition.
(thesaurus)
Can you help me to learn more?
(Other definitions for undercover that I've seen before include "Agent's description" , "How a book may be found" , "Hidden" , "Clandestine" , "What spy may be" .)