"Heart of Darkness" is a very involved story, which takes place on a mission into the hearts of Africa. The use of imagery in "Heart of Darkness" gives the story another dimension of insight. Joseph Conrad's use of imagery is so compelling because everything in the story symbolizes, alludes to, or allegorizes something in some way. As William Rogers II from the San Diego State University states, "Yet, as Wilfred Dowden's recent study of Conradian imagery concludes, the some 1,100 words of the unnamed narrator that precede Marlow's tale are not merely an accessible lead in to the subsequent complexity of narration and theme but are carefully composed to establish imagery and tonality for the entire work." (Rogers, page 42) Joseph Conrad uses imagery in his descriptions of the surroundings, with the use of light and darkness and other objects in "Heart of Darkness" to better express his ideas throughout the story. .
One of the main themes in "Heart of Darkness" is colonialism in Africa. During the time of this story Europeans were invading Africa and enslaving the people who lived there. Throughout the story Conrad gives references to this. For example, "I could see every rib, the joints of their limbs were like knots in a rope; each had an iron collar on his neck, and all were connected together with a chain whose bights swung between them, rhythmically clinking."(Page 280) Conrad also uses imagery to highlight the darkness of these acts. For example when the narrator gives a description of the areas surrounding him he uses darkness, death, and words of dejection to explain the images he sees. "They were not enemies, they were not criminals, there were nothing earthly now, - nothing but black shadows of disease and starvation, lying confused in the greenish gloom." (Page 281) Also the author uses the words "heart of darkness" to describe his surroundings. These words imply to the reader the darkness at the center of Africa, with all the evil and death surrounding the people there.