V Season 3 Episode 8 The Dissident

Robin is in love with Kyle, but Kyle wants to go out with Elizabeth. Diana puts up a force field around Los Angeles that disintegrates anything that comes into contact with it. Of course she gives a code to Nathan Bates, which Julie steals. Meanwhile, Mike and Ham kidnap the Visitor scientist who made the force field. Jacob the scientist is a pacifist and uses a magic ring to destroy the force field and himself.