An exploration of the effect of music on the brain via four case studies from neurologist Oliver Sacks book "Musicopia" and the MRI visualizations from Sacks' own brain as classical music is played, including Bach's "Mass in B Minor." Study subjects include a man with Tourettes syndrome who has found relief while playing the drums; an autistic savant who is simply dazzling on the piano; a woman who suffers the inability to process music, known as amusia; and a surgeon whose life changed after being struck by lightning.