1. WHO Compound, Kinshasa

A series of sun flares, powerful enough to leave the world in darkness, causes a mutation in a strain of ebolavirus. Now airborne, the virus spreads through Central Africa and leaves survivors in complete isolation. 4 months later, in the now-deserted city of Kinshasa, a CDC epidemiologist develops a cure, and must make his way across the continent towards the sea, in the hope of getting in contact with civilisation.