Commander Geoffrey Peace, an ex-Submarine commander is seconded to MI6 and sent undercover to South Africa to check on an ultra-right wing Afrikaner group who are active in gold-mining and thought to have a gold bullion shipment en route to Britain. This group have acquired nuclear weapons before those in the South African arsenal were dismantled. MI6 have reason to believe that these weapons have been secreted away in a mine in the desert.
