Devil's Eyes

S1, E13: Having discovered that Helena is Huntress, Harley uses a machine that gives her metahuman hypnotic powers. She then hypnotizes Helena and persuades her to knock Barbara unconscious and steal an access disk. Barbara recovers and uses her subneural device to enable her to stand and fight Helena, eventually neutralizing the trance. But Harley uses the disk to gain complete control of the clock tower and, after killing Wade (recurring guest star Shawn Christian), she broadcasts the hypnotic signal to every television set in New Gotham. Working together with Alfred, Dinah and Reese, Helena must infiltrate the clock tower and battle Harley and her cohorts before they gain control of the entire city.