While rehearsing a play, Penny, the Robot and Dr. Smith are interrupted by a hideous alien. Dr. Smith flees, but the Robot announces that the alien is not hostile. Penny befriends him, and the alien transforms itself into a life form that can exist on that planet. He introduces himself as Arcon, and when he reveals he is being pursued by the Saticons seeking a powerful amulet he holds, Penny offers him sanctuary at the Jupiter 2.