Revenue from Angola's oil reserves should be aiding the country's development. But instead, it's being used as a slush fund for government corruption. Deep in Luanda's sewers, a group of boys show us around their home. "I'm desperate for help," begs one. "I'm eating rubbish, surrounded by others who are sniffing glue." According to the latest calculations, 9% of the country's GDP is siphoned off. Even the US ambassador admits that oil revenues are not going to "the Angolan people." Ordinary Angolans know they're being ripped off by their leaders. They're seething with resentment. In the Angolan enclave of Cabinda, this discontent has fuelled a separatist movement which has been fighting for years. With more and more Angolans asking awkward questions, there's a risk the country will collapse into anarchy again if the corruption problem isn't addressed.