Programme two looks at the 1960s folk boom, when the hippie generation repackaged folk music to appeal to a wider audience.
A new breed of virtuoso guitarist - such as Davy Graham and Bert Jansch - became the heroes of the movement as folk clubs, run by young people for young people, sprang up all over the country.
In 1965, Britain produced its first folk pop star in the form of Donovan - who embraced bohemia and turned his back on society, "challenging hypocrisy and greed." Later the same year, Bob Dylan polarised folk fans by going electric.
But there was still a mood for experimentation. In Scotland, the Incredible String Band fused folk with psychedelia while Pentangle explored the possibilities of jazz-folk.
Folk-rock entered the mainstream - Lindisfarne's Fog on the Tyne spent 54 weeks in the charts - but by the mid-1970s the genre had become a parody of itself.