[The first synopsis is a far shorter summary of the film with more of a historical context; appearing a few paragraphs down is a second, "chronological" synopsis of the film.]
Set in the early 1950s in Saigon, Vietnam, during the end of the First Indochina War, on one level The Quiet American is a love story about the triangle that develops between a British journalist in his fifties, a young American idealist and a Vietnamese girl, but on another level it is also about the political turmoil and growing American involvement that led to the Vietnam War.
Fowler, who narrates the story, is involved in the war only as an observer, apart from one crucial instant. Pyle, who represents America and its policies in Vietnam, is a CIA operative sent to steer the war according to Americas interests, and is passionately devoted to the ideas of York Harding, an American foreign policy theorist who said that what Vietnam needed was a third player to take the place of both the colonialists and the Vietnamese rebels and restore order. This third player was plainly meant to be America, and so Pyle sets about creating a Third Force against the Viet Minh by using a Vietnamese splinter group headed by corrupt militia leader General Thé (based on the actual Trinh Minh The). His arming of Thé's militia with American weaponry leads to a series of terrorist bombings in Saigon. These bombings, dishonestly blamed on the Communists in order to further American outrage, kill a number of innocent people, including women and children.
Meanwhile, Pyle has stolen Fowlers Vietnamese mistress Phuong, promising her marriage and security. When Fowler finds out about Pyle's involvement in the bombings, he takes one definitive action to seal all of their fates. He indirectly agrees to let his assistant, Hinh, and his Communist cohorts confront Pyle; when Pyle tries to flee, Hinh fatally stabs him. Phuong subsequently returns to Fowler, and while the local French police commander suspects Fowler's role in Pyle's murder, he has no evidence and does not pursue the matter. [D-Man2010]
It is Saigon in the early 1950s. Thomas Fowler (Michael Caine) is a writer for the London Times, and he is covering the conflict between the Communists and the French in Indo-China (Vietnam). He is asked to identify the body of Alden Pyle (Brendan Fraser). Most of the rest of the film is a flashback. Fowler remembers how he met Pyle at the Hotel Continental in Saigon. He remembers that when he met him, Pyle was an enthusiastic and idealistic member of a medical aid team. Fowler next gets a telegram from his editor ordering him to return to London. Fowler writes a story about Phat Diem, which is a village being attacked by the Communists with the hope of getting his editor to let him stay. Fowler introduces his girlfriend, Phuong (Do Thi Hai Yen), to Pyle. At a dance hall, Pyle dances with Phuong. He tells her that he can only speak two words in Vietnamese, beer and haircut. Her older sister (Pham Thi Mai Hoa) hopes to get Phuong attached to Pyle, who she obviously considers a better match than Fowler. Fowler tells Phuong that he must return to London, but that he cant get a divorce from his wife.
Later, Fowler is with soldiers investigating Phat Diem, when Pyle appears in a boat, surprising everyone. They find the villagers massacred. That night, Fowler and Pyle are together, and Pyle tells Fowler that he has fallen in love with Phuong. Pyle returns to Saigon first, and when Fowler returns to Saigon he watches a parade to honor General The (pronounced Tay; Quang Hai), who is the leader of a new political party. Afterwards, Pyle comes to Fowlers house, and he proposes to Phuong, but she rejects him, and he leaves.
Fowler's editor now wants him to stay in Saigon on account of his story about the massacre. He writes to his wife seeking a divorce, and he tells Phuong that he is doing so. Much later, Fowler drives to the front to interview The and is surprised to see Pyle with his medical team. Fowler can't get to see The, but Pyle arranges an interview for him. Fowler angers The with his questions, and the interview ends. Fowler and Pyle leave together in Fowlers car. Apparently, the Vietnamese have siphoned the gas from Fowlers car, and it runs out of gas on the way back to Saigon. They are in a tower in a village when the village comes under attack. Fowler hurts his ankle, and Pyle goes for assistance. In a further flashback, Fowler remembers how he first met Phuong at a dance hall.
Pyle returns and they go back to Saigon. Phuong welcomes Fowler back and gives him a letter from his wife. Fowler tells Phuong that his wife has given him a divorce. However, later, Pyle, Phuong and her sister accuse Fowler of lying about the divorce. Fowler and his Vietnamese colleague, Hinh (Tzi Ma), uncover a shipment of diolacton at a warehouse. They dont know what diolacton is.
Phuong leaves Fowler for Pyle. Subsequently, Fowler is sitting on the porch of the Continental Hotel. There is a terrific explosion, and horrific death and injuries. Fowler, in a daze, tries to help. He sees Fowler at the scene. Later, he realizes that Pyle was speaking Vietnamese. Fowler finds out that diolacton is used to make explosives, and he figures out that the Americans are supplying The with explosives. Hinh informs Fowler that Pyle works for the CIA. At Hinh's suggestion, Fowler invites Pyle to his house. Pyle brings his dog with him. Pyle defends The as someone who can inspire the people and stop the advance of Communism. Fowler arranges to meet Pyle at a restaurant that evening. We next see him sitting at the restaurant outdoors, and he watches Pyle cross a bridge with his dog. We next see Pyle kidnapped by Hinh's men with knives. Later, he escapes from them and is running away when he is re-captured by one of the men who stabs him to death. After seeing Hinh leave the area, Fowler leaves the restaurant. Later, the policeman suggests that Pyle had been to see Fowler because Pyles (also) murdered dog had cement from the floor of Fowlers house on its paws. Fowler tells the police that he didnt kill Pyle, and "there is a war on and people are dying every day." It is not clear whether Fowler set up the murder to help Hinh stop the CIA's involvement in Vietnam or to kill his girlfriend's lover, or (most likely) both.
In the end, Fowler goes back to the dance hall and tries to get Phuong to dance with him. Phuong tells him to dance with someone else, until he tells her that he will never leave. Fowler says that he feels a need to apologize to someone, but Phuong says "not to me, never to me." Afterwards, news headlines show the beginning and full-fledged advance of the American involvement in the Vietnam war. Its not clear whether we are supposed to think that Fowler's helping Hinh murder Pyle led to the American war in Vietnam.