Sir Trevor continues his epic journey through the heartland of the USA following the course of its most famous and important river, the Mississippi. This week the river's influence on the twentieth century comes to the fore as he meets Hollywood "A" lister Morgan Freeman and discovers why he returned to his roots in Mississippi after forty years away. In Memphis, the site where Dr Martin Luther King was assassinated is shown to Sir Trevor by Rev. Kyles who was stood by King's side when he was shot. And he meets a former girlfriend of Elvis Presley who gives him a candid portrait of the King of Rock and Roll just as he was starting his phenomenal rise to fame.