Beyond Nashville.
Although country music is often seen as representing the forces of conservatism and tradition, it has a left-field streak. Tonight's episode focuses on the mavericks who reinvented country for their eras. It takes in the Bakersfield sound of Buck Owens and Merle Haggard, the outlaw music of Willie Nelson and Waylon Jennings and the alternative country movement of today.
BBC book: The Story of Country Music by Colin Escott, £16.99