Marlow is an experienced seaman who secures a job captaining a river steamboat for a Belgian ivory trading company. Driven by a childhood fascination with the blank spaces on maps, he travels to the Congo. He observes the operations of the colonial system with a sense of weariness, focusing strictly on his work to maintain personal distance from the cruelty around him.

Kurtz is a highly successful ivory agent stationed deep in the Congo interior. He reportedly brings in more ivory than all other agents combined and is viewed by the Company as a prodigy destined for high management. A man of immense eloquence, he operates completely free from the constraints of European society and standard morality.

The Russian Trader is an eccentric, wandering seaman who has spent two years living in the deep jungle. He functions as an independent operator, sending back minimal ivory to avoid trouble while dedicating his life to following Kurtz. He is entirely captivated by Kurtz's rhetoric and refuses to judge the agent by standard human metrics.

The General Manager oversees the Company's Central Station. He is an unwholesome man of average abilities whose primary skill seems to be outliving his competitors. He maintains his position through causing unease rather than earning respect, prioritizing short-term ivory profits and corporate standing over all else.

The Brickmaker is an ambitious Company employee stationed at the Central Station who produces no actual bricks. He operates as the General Manager's spy and attempts to extract information from Marlow, wrongly assuming Marlow possesses high-level corporate connections.

Marlow's aunt is a well-connected woman living in Europe who uses her influence to get her nephew a position with the Company. She firmly believes the colonial enterprise is a noble crusade meant to bring civilization to the world, completely detached from its harsh economic realities.

The Chief Accountant is a Company employee stationed near the coast. Despite the chaotic and decaying conditions of the Outer Station, he maintains an immaculate, heavily starched European wardrobe and focuses entirely on keeping his books in perfect order.

An anonymous former sailor who listens to Marlow's tale aboard a cruising yawl on the Thames. He serves as a typical European listener, passively absorbing the story while framing the narrative for the reader.

A local man trained by the Europeans to steer the steamboat and manage its boiler. He is a pragmatic worker whom Marlow observes closely during the tense journey up the Congo River.

A local African woman adorned in striking ornaments who maintains a close connection with Kurtz. She commands a powerful presence at the Inner Station and exhibits intense devotion to him.

Kurtz's intended bride remains entirely devoted to his memory in Europe. She holds onto an idealized, flawless vision of the man she loves, representing the sheltered illusions maintained by European society.

The Uncle leads a band of men hoping to extract treasure from the land without any moral pretense. He conspires secretly with his nephew regarding the ongoing situation with Kurtz upriver.