The story tells of Charles Marlow, an Englishman who took a foreign assignment from a Belgian trading company as a ferry-boat captain in Africa. Although Conrad does not give the name of the river, at the time, Congo Free State, the location of the large and important Congo River was a private colony of Belgium’s King Leopold II. Marlow is employed to transport ivory downriver. However, his more pressing assignment is to return Kurtz, another ivory trader, to civilization, in a cover-up. Kurtz has a reputation throughout the region.This symbolic story is a story within a story or frame narrative. It follows Marlow as he recounts from dusk through to late night, to a group of men aboard a ship anchored in the Thames Estuary his Congolese adventure. The passage of time and the darkening sky during the fictitious narrative-within-the-narrative parallel the atmosphere of the story. Wikipedia