Buster is convinced that he's seen real UFO's, and he uses Muffy's fan cy new telescope to get the proof. What he discovers is much more terr ifying-a comet hurtling directly toward earth! Can Buster convince his friends that this sighting is real in time for them to save the plane t? Mr. Sipple from next door is moving away and Arthur wonders-who wil l be the new neighbors? When Alberto Molina and his family settle in, Arthur makes a new friend and learns about a different culture...and a bout a comic book character named Conejitos Mechanicos! (That's Spanis h for Bionic Bunny)