<P> Catherine Tramell is a fictional character and main antagonist in the film Basic Instinct ( 1992 ) and its sequel , Basic Instinct 2 ( 2006 ) . Catherine , created by writer Joe Eszterhas , is played by Sharon Stone in both films . In Basic Instinct , Tramell is a serial killer and love interest of washed - up detective Nick Curran ; Basic Instinct 2 pairs her with the similarly troubled British psychologist Michael Glass . </P>
who is the real killer in basic instinct 2
Catherine Tramell