Conspirator (7)
I believe the answer is:
plotter
<span class="explanation-format__ClueExplanation">'<span class="explanation-format__original">conspirator</span>' is the definition.<br/ ><span class="explanation-format__explanation">(synonyms)</span><br/ ><br/ >This is all the clue.<br/ ></span>
(Other definitions for plotter that I've seen before include "Schemer" , "Conspirator" , "Conspirator's" , "One who schemes" .)