King gripped by novel about woman in service (4)
I believe the answer is:
Here is my best explanation:
'woman in service' is the definition.
'Wren' can be an answer for 'woman'. I'm not certain of the 'in service' bit.
'king gripped by novel about' is the wordplay.
'king' becomes 'r' (r is abbreviation for rex).
'gripped by' indicates putting letters inside.
'novel' becomes 'new' (synonyms).
'about' is a reversal indicator.
'r' placed into 'new' is 'nerw'.
'nerw' in reverse letter order is 'WREN'.