Agatha Christie's detective (6)
I believe the answer is:
poirot
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">agatha christie's detective</span>' is the definition.<br/ ><span class="explanation-format__explanation">(I've seen this before)</span><br/ ><br/ >This is the entire clue.<br/ ></span>
(Other definitions for poirot that I've seen before include "... and her male one" , "10 [SLEUTH]" , "Hercule -, detective (Agatha Christie)" , "Hercule . . . . . ., Agatha Christie's detective" , "Agatha Christie's Belgian detective" .)