There is a new BBC TV history series by Simon Schama, The Story of Us.

In the first programme Simon highlights the huge impact that Alan Sillitoe's novel 'Saturday Night and Sunday Morning' had when it was published in 1958.

Alan Sillitoe spoke to David Freeman when his novel Birthday was published in 2001.

Birthday is the sequel to Saturday Night and Sunday Morning.

1958 to 2001 is a ling time to wait for a sequel.

So why did it take so long?