Two years ago, country music legend Glen Campbell was diagnosed with Alzheimer's disease and told to prepare for the worst. Instead, Glen and his wife went public with the diagnosis and set out on a 'Goodbye Tour'.

'Glen Campbell I'll Be Me' tells the story of the shows, and a great cast of contributors includes Bruce Springsteen, Paul McCartney, Sheryl Crow, Taylor Swift and Edge.

'The audience being there somehow triggers his ability to access that other part of his brain... which is incredible.'