One of the most enigmatic characters in twentieth-century literature, Kurtz is a petty tyrant, a dying god, an embodiment of Europe, and an assault on European values. These contradictory elements combine to make Kurtz so fascinating to Marlow — and so threatening to the Company.
Like Marlow, Kurtz also wished to travel to Africa in search of adventure — specifically, to complete great acts of "humanizing, improving, instructing" (as he explains in his initial report to the Company). Once he tasted the power that could be his in the jungle, however, Kurtz abandoned his philanthropic ideals and set himself up as a god to the natives at the Inner Station. While he used to worry about the best ways to bring (as his painting demonstrates) the "light" of civilization to the Congo, he dies as a man believing that the Company should simply "Exterminate all the brutes!"
Kurtz is a dangerous man because he gives the lie to the Company's "humanistic" intentions in the Congo. He returns more ivory than all the other stations put together, and does so through the use of absolute force. This frightens men like the Manager, who complains of Kurtz's "unsound method" — although Kurtz is only doing what the Company as a whole is doing without hiding his actions behind a façade of good intentions. Marlow remarks that "All Europe contributed to the making of Kurtz," and Kurtz's very existence proves this to be true: Like the Europeans involved in enterprises such as the Company, he epitomizes the greed and lust running wild that Marlow observes in the Congo. However, unlike the Company, Kurtz is not interested in his image or how he is perceived by "noxious fools" such as the Manager. While Brussels is a "whited sepulcher" of hypocrisy, Kurtz is completely open about his lusts. He tells the Manager he is "Not so sick as you'd like to believe." But this statement is applicable to all Europeans involved in imperialistic empire-building: While labeling Kurtz a morally "sick" man might seem comforting, he is actually an exaggeration of the impulses harbored in the hearts of men everywhere.