>> the question of whether ruby knew oswald before or was in cahoots to kill him is one of the most important questions. because ruby knew people in criminal activities, there was a lot of investigation about a potential conspiracy. >> ruby would have been one of the most unlikely and worst hit men that the mob could ever get. >> on november 24th, 1963, lee harvey oswald is supposed to have been transferred at 10:00. at 10:00, the evidence is undisputed that jack ruby was at home asleep. then he got dressed and drove downtown. >> the receipt shows that ruby was sending a money order to one of his strippers from a western union office across from the courthouse at 11:17 a.m. >> we know that at 11:20, three minutes later, a block away, jack ruby killed lee harvey oswald. the evidence showed that he was down there anywhere from 5 to 15 seconds. 5 to 15 seconds. if this is a hired assassin who is supposed to have some advanced information, he is the world's best gunman.