From the author: It was the giant of Africa: a nation which once represented the greatest hope for peaceful coexistence between Arab and African, Muslim and Christian. That hope is all but gone. The promise of Sudan was just an illusion.It is already a fractured country and, in the longer term, this is unlikely to be an isolated matter of north and south breaking apart following the referendum on southern secession.Separatist movements in regions such as Darfur and the Nuba Mountains are watching with more than curiosity. And it is not just Sudan: in other African and Arab countries independence factions are eying developments with a view to making their move either through the ballot box or the gun.In the run-up to the referendum, I traveled to Sudan to make the film. I have been fortunate enough in my life to have visited most of the world's countries and yet, this would be the first time I had set foot in Africa's largest.To say that the northern Sudanese people are enormously friendly may be cliched, but it is also very true. Soon after our arrival, the car we had hired in Khartoum broke down and we quickly found ourselves surrounded by young men, all of them trying to help discover and rectify the fault. No-one was looking for money; it simply came naturally to them to help out and was just one example of many we would discover in the following weeks.Unfortunately though, I also discovered self-delusion: in the coffee shops, restaurants and streets, the vast majority of people I spoke with wanted desperately to believe that it was not too late and that, surely, the South will never leave the union. It will.