Francis Ford Coppola's Apocalypse Now lacks the impact of its inspiration; Joseph Conrad's Heart of Darkness. While the basic elements of imperialism and human nature remain intact, the characters of the film bare little resemblance to their literary counterparts. The film serves as a re-interpretation of Conrad's novella, updated from 19th-century British imperialism in the Congo to a critique of 20th-century U.S. imperialism in Southeast Asia. Coppola's changes in setting and plot structure, however, force the film to sacrifice the character development so crucial in the literary work, ultimately detracting from the overall effectiveness of the film.
The most important difference between novella and film is the development of their main characters, Marlow and Willard, respectively. In Heart of Darkness, the reader is introduced to Marlow through his various philosophical ruminations about imperialism, morality, and human nature. Learning of the mysterious Kurtz through first-hand accounts of his accomplishments and bizarre behavior, Marlow spends more and more time in the jungle. Due to this increasing time in the jungle, his pre-occupation with Kurtz becomes an important refuge from the brutality of the Belgians for whom he works. Although critical of the Belgian bureaucracy, it is unclear whether his displeasure stems from their immoral practices or their incompetence and inefficiency. Conrad never reveals Marlow's true feelings, forcing the reader to confront the issues of racism and human nature themselves. .
Willard, on the other hand, is a psychological mess from the beginning of the film. The opening scenes depict him confessing his own mental imbalances as a result of prolonged service in the Vietnam War. While Conrad's Marlow borders on complacency, Coppola's Willard behaves erratically and without reason. His fascination with Kurtz is also less profound than in Heart of Darkness.