 " Episode 6188 " is the <unk> episode of the Australian soap opera Neighbours . It premiered on Eleven on 22 June 2011 . The episode was written by Sarah Mayberry , directed by Jonathon Dutton , and executively produced by Susan Bower . " Episode 6188 " revolves around Mark Brennan 's ( Scott McGregor ) departure from the soap . The storyline sees Mark tell his girlfriend , Kate Ramsay ( Ashleigh Brewer ) , that he is going into witness protection . He reveals that she has just 30 minutes to decide whether to stay behind in Erinsborough or leave with him . However , when she makes the choice to leave , she has trouble convincing her younger sister to come too . 
