Johnny Cash once called 1968 the happiest year of his life. It was the year his masterpiece At Folsom Prison came out, the year he was named the Country Music Association’s Entertainer of the Year, and the year he married the love of his life, June Carter. So it was a fortunate time for a young filmmaker named Robert Elfstrom to meet up with Cash for the making of a documentary. Elfstrom traveled with Cash for several months in late 1968 and early 1969. The resulting film, Johnny Cash: The Man, His World, His Music, is a revealing look at Cash, his creative process and his ties to family.