Writer on working with lady during chapter one (5,5)
I believe the answer is:
conan doyle
'writer' is the definition.
(I've seen this before)
'on working with lady during chapter one' is the wordplay.
'working with' indicates anagramming the letters (working with the letters).
'during' means one lot of letters goes inside another.
'chapter' becomes 'c' (abbreviation).
'on' anagrammed with 'lady' makes 'andoyl'.
'c'+'one'='cone'
'andoyl' going inside 'cone' is 'CONAN DOYLE'.
(Other definitions for conan doyle that I've seen before include "A Study in Scarlet author" , "popular author" , "Sherlock Holmes author" , "The Lost World author" , "mystery writer" .)