Plot summary

" Saigon, shit. I'm still only in Saigon." The journey into the heart of darkness begins in a hotel room in Saigon, Vietnam. US Army Captain Willard (Martin Sheen) of 505. battalion, 173 Airborne, assigned SOG, also an CIA operative and an assasin, is waiting for an mission. He is haunted by his earlier deeds and he is getting very drunk. Willard smashes the mirror while fighting himself and cuts his hand. He collapses on the bed weeping.

In the morning Willard is brought from the hotel to a briefing in Nha Trang. At present are General Corman, Colonel Lucas (Harrison Ford) and a civilian (Jerry Ziesmer, assistant director of the film) . He receives orders to infiltrate renegade special forces Colonel Kurtz's troops and terminate his command. "Terminate with extreme prejudice." Kurtz is said to have gone totally insane, he runs his own private army in the jungle in Cambodia and is worshipped as a god by a native tribe. Kurtz is charged of executing vietnamese intelligence agents who he said were double agents. Kurtz' troops are however very successful in fighting North Vietnamese and Vietkong but his methods are considered to be "unsound". 

Willard travels to Kurtz's camp up Nung river to Cambodia in a Navy patrol boat with a rather weird boat crew : Mr.Clean, a guy from Bronx. " Light and space of Vietnam really put the zap on his brain." Chef, a real chef, a saucier, from New Orleans, a very nervous guy. Lance Johnson, a well known surfer from Los Angeles and Chief Philips, the commander of the boat. On this surrealistic journey a lot of strange things happen. Willard is being helped by a manic air cavalry commander Lieutenant Colonel Kilgore ( Robert Duvall ), who really loves surfing. His troops blow up a Vietkong village, with Wagner's Ride of the Valkyries blasting from the speakers, to help Willard but mostly because there are pretty good waves and he wants to see Lance surfing. After calling a napalm attack on Vietkong troops in the jungle Kilgore confesses his love for the smell of napalm. And, yes.. Charlie don't surf ! 

After this ordeal the journey continues to a navy base by the river. They get more supplies and witness a chaotic and absurd show by Playboy playmates in the middle of nowhere. In the boat Willard reads Kurtz' dossier. There is a letter Kurtz has sent to his son, where he explains his actions :

Dear son, 

"I'm afraid that both you and your mother would have been worried for not hearing from me these past weeks. But my situation here has become a difficult one. I've been officially accused of murder by the army. The alleged victims were four Vietnamese double agents. We spent months uncovering and accumalating evidence. When absolute proof was completed, we acted, we acted like soldiers. The charges are unjustified. They are in fact, under the circumstances of this conflict quite completely insane. 

In a war there are many moments for compassion and tender action. There are many moments for ruthless action, for what is often called ruthless. But many and many circumstances, the only clarity; seeing clearly what there is to be done and doing it directly, quickly, awake... , looking at it.

I would trust you to tell your mother what you choose about this letter. As for the charges, I'm unconcerned. I'm beyond their lying morality. And so I'´m beyond caring.

You have all my faith.

Your loving father."

The following scene is one of the most powerful in the movie. They stop a sampan of Vietnamese civilians and start to search it. A girl makes a move towards one basket and the soldiers panic and start to fire wildly, killing everybody onboard. The girl was however only wounded, but Willard coldly executes her. It turns out there was only a puppy in the basket. Lance adopts this symbol of innocence.

The next stop is Do Lung bridge, the last military base by the river. "Beyond that there's only Kurtz." This place is really in chaotic state, " the asshole of the world ". The boat is met by a group of soldiers who desperately want to leave the place, Willard wants to get more intelligence of the situation but can't find any commanding officer there. He gets though a briefing file sent to him . He learns that previously one man, Captain Richard Colby (Scott Glenn) was assigned for the same job, but now he is believed to have joined Kurtz's troops. 

On the way to Kurtz's base, Clean gets shot in an ambush by Vietkong and later Chief is killed by a spear in a native tribe attack. Finally Willard, Chef and Lance arrive to Kurtz's temple and are met by a weird scene. A number of natives, Montagnards, in boats meet them first , they see a lot of bodies hanging in the trees and a large collection of heads. An american photojournalist (Dennis Hopper), a jester in Kurtz's court, who idolises Kurtz as a great guru, welcomes them to the camp. Captain Colby is also among Kurtz' troops. Willard is later brought to meet Kurtz and in a brief conversation he tells Willard that he knows he has come to kill him. " You're an errand boy, sent by grocery clerks to collect a bill. " Willard is then locked in a cage and in the night Kurtz visits him and drops Chef's head in his lap. After this Willard is free to move around in the camp, he listens when Kurtz reads poems  ( T.S. Eliot's Hollow Men ) and delivers his horror monologue :

" I've seen horrors...horrors that you've seen. But you have no right to call me a murderer. You have a right to kill me. You have a right to do that...But you have no right to judge me. It's impossible for words to describe what is necessary to those who do not know what horror means. 

Horror. Horror has a face...And you must make a friend of horror. Horror and moral terror are your friends. If they are not then they are enemies to be feared. They are truly enemies.

 I remember when I was with Special Forces...Seems a thousand centuries ago...We went into a camp to innoculate the children. We left the camp after we had innoculated the children for Polio, and this old man came running after us and he was crying. He couldn't see. We went back there and they had come and hacked off every innoculated arm. There they were in a pile...A pile of little arms. And I remember...I...I...I cried...I wept like some grandmother. I wanted to tear my teeth out. I didn't know what I wanted to do. And I want to remember it. I never want to forget it. I never want to forget.

And then I I was shot...Like I was shot with a diamond...a diamond bullet right through my forehead...And I thought: My God...the genius of that. The genius. The will to do that. Perfect, genuine, complete, crystalline, pure. 

And then I realized they were stronger than we. Because they could stand that these were not monsters...These were men...trained cadres...these men who fought with their hearts, who had families, who had children, who were filled with love...but they had the strength...the do that. If I had ten divisions of those men our troubles here would be over very quickly. You have to have men who are moral...and at the same time who are able to utilize their primordal instincts to kill without feeling...without passion...without judgement...without judgement. Because it's judgement that defeats us. "

Kurtz is worried that his son wouldn't understand the things he has done and he wants Willard to explain everything he has witnessed to him if Kurtz is to die. " ... because there is nothing I detest more than the stench of lies. So he accepts the fact that he will be killed by Willard and death will come as a relief to this troubled man. " Everybody wanted me to do it, him most of all. I felt like he was up there, waiting for me to take the pain away. He just wanted to go out like a soldier, standing up, not like some poor, wasted, rag-assed renegade. Even the jungle wanted him dead, and that's who he really took his orders from anyway. "

The movie ends with a spectacular scene. During a native tribe's ritual sacrifice seremony of a water buffalo, The Doors' The End playing on the background, Willard finally kills Kurtz with a machete. His final words are "The horror. The horror !" Willard finds a Kurtz's manuscript where he has written his last wish: "Drop the bomb. Exterminate them all." The Fisher King legend : man kills the king and becomes the king himself. But Willard doesn't want any of this. The natives worship him, their new king, but Willard drops the machete and walks away. The movie ends when Willard and Lance leave the camp with the boat. 

  " The offing was barred by a black bank of clouds, and the tranquil waterway leading to the uttermost ends of the earth flowed sombre under an overcast sky - seemed to lead into the heart of an immense darkness. "
Joseph Conrad : Heart of Darkness