i've got to tell you this one. you know those knock-knock jokes? >> yeah, but they're old now. >> yeah. i've got a real good one. i've got a really funny one. >> all right. >> go ahead. start. say "knock, knock." >> i say it? >> yeah, go ahead. >> knock, knock. >> who's there? >> there was only three networks. there was only one late night show, really, and it was jack paar. >> they don't understand how we do this show. we just keep talking with no script. >> i know. it's agony. [ laughter ] >> jack paar invented the late night television talk show. >> you feel confident? >> there is not a man in the world to beat me. i'm as pretty as liberace. [ laughter ] >> jack had in his corner his personality. his fabulously, interesting,