Wonderful person, married woman, gripped by desire (9)
I believe the answer is:
humdinger
'wonderful person' is the definition.
(humdinger can mean a remarkable person or thing)
'married woman gripped by desire' is the wordplay.
'married' becomes 'm'.
'woman' becomes 'di' (short for Diana).
'gripped by' is an insertion indicator.
'desire' becomes 'hunger' (hungering is a kind of desiring).
'm'+'di'='mdi'
'mdi' put inside 'hunger' is 'HUMDINGER'.
(Other definitions for humdinger that I've seen before include "remind -ugh- of remarkable person or thing" , "Excellent example" , "One's brilliant" , "knockout" , "Something really good" .)