What is it that makes a song achieve mass appeal?
The series Greatest Hits of the World examines two enduring songs that have crossed boundaries and generations.
In the second programme, Paul Gambaccini looks at the song Wimboweh or The Lion Sleeps Tonight by South African songwriter Solomon Linda.
From 1939 the melody sold 100,000 copies in its first decade.
The tune - originally called Mbube (Zulu for lion) - may never have left Africa, but it came to the attention of American folk singer Pete Seeger.
His interpretation was so popular and so catchy that a number of versions appeared throughout the 1950s by other American singers.
Other versions have appeared since, including one by The Tokens, a group that added the distinctive lyrics. In the 1990s, it was exposed to a mass audience with its inclusion in the Disney film The Lion King.
The song is estimated to be worth $16 million.
But Solomon Linda was paid a one off fee of 10 shillings and he died in poverty in 1962.
What is the story of the search for social justice behind the song?
First broadcast on 16 July 2010.