One actor, Irish, featuring in British books and play (6,6)
I believe the answer is:
'play' is the definition.
(I've seen this before)
'one actor irish featuring in british books' is the wordplay.
'one actor' becomes 'thesp' (short for thespian, term for an actor).
'irish' becomes 'IR' (abbreviation).
'featuring in' is an insertion indicator.
'british books' becomes 'bliit' (I can't explain this - if you can you should give a lot more credence to this answer).
'thespir' going into 'bliit' is 'BLITHE SPIRIT'.
'and' acts as a link.
Can you help me to learn more?
(Other definitions for blithe spirit that I've seen before include "Phil is bitter (anag) - Noel Coward play" , "written for a lark by poet" , "Comedy" , "Coward acts" , "Noel Coward play (Madame Arcati)" .)