Dan Aykroyd played an alien in 'The Coneheads,' but now he says he believes in UFOs. For the very first time, Aykroyd is sharing his experiences in a new DVD called 'Dan Aykroyd: Unplugged on UFOs.' COSBY: Dan, do you believe that there's a massive government cover-up about UFOs? AYKROYD: I think [UFOs are] here, and I think some want to make life on this planet better, to end violence and end abuse of our environment. COSBY: We're joined by...Dr. Bruce Maccabee. He is a Ph.D. with the Mutual UFO Network. And with me here in the studio is Michael Luckman...the director of the New York Center for Extraterrestrial Research.MACCABEE: The documents show that, as early as the early 1950s, the Air Force intelligence concluded that there was a definite possibility that interplanetary ships were being sighted by literally hundreds of people. COSBY: There's a new poll...that says that 14 percent...claim to have had an encounter or know someone who has. COSBY: Do you believe that there are UFOs? LUCKMAN: Absolutely. The proof is [in] hundreds of thousands of formerly top secret documents that have been pried out of the government as a result of the Freedom of Information Act. The smoking gun...lies in about 200 former military [and] intelligence people. I have copies of videotaped depositions that were done with these gentlemen. I am convinced that they're telling the truth about their knowledge, and they're willing to go public.