In 1965, President Lyndon B. Johnson increases U.S. military forces in the Vietnam War. Airman Adrian Cronauer is transferred from Crete to Saigon, Vietnam, to be a disc jockey for Armed Forces Radio Saigon. Arriving at the airbase, Cronauer is met by Private First Class Edward Garlick, who works as an aide at the radio station. Garlick introduces the new deejay to his superiors, Lieutenant Steven Hauk, Sergeant Major Dickerson, and General Taylor, a fan of Cronauer’s humorous radio show in Crete. The surly Sgt. Maj. Dickerson reprimands Cronauer for not being in uniform, and warns him not to misbehave. Cronauer begins his first show by bellowing, “Good morning, Vietnam!” – a greeting that becomes his trademark. He pretends to interview servicemen in the field, shifting rapidly between characters, and plays rock n’ roll records that Lt. Steven Hauk frowns upon. After the show, Hauk warns Cronauer not to make fun of the weather, and suggests that he stick to “normal modes of music” from the likes of Lawrence Welk, Andy Williams, and Frank Sinatra. Cronauer ignores Hauk’s orders and stays true to his broadcasting style. While drinking at Jimmy Wah’s, a G.I. bar in town, Cronauer notices a beautiful young woman on the street and follows her to her English class, taught by an American serviceman. Cronauer bribes the man to let him teach, instead. He employs his comedy routine to teach the students English slang. When class is over, he tries to talk to the young woman, whose name is Trinh, but her younger brother, Tuan, stops him. Tuan believes that American men cannot be trusted with Vietnamese women. Cronauer befriends the boy, and takes him to Jimmy Wah’s, where they join Garlick, and Radio Saigon deejays Marty Lee Dreiwitz, Dan “The Man” Levitan, and Phil McPherson. The men notice attractive Vietnamese women flirting with two sergeants at the bar. Cronauer lures the women to their table, and the sergeants confront him and Tuan. They refer to Tuan as a “gook” and demand that he leave. Cronauer comes to Tuan’s defense and incites a brawl. Dickerson reprimands him for the incident, and threatens to reassign him. Over time, Cronauer becomes frustrated with the radio station censors, who determine what news is acceptable for broadcast, and generally forbid anything having to do with the war. He continues to teach Trinh’s English class, and she finally agrees to a date. However, they are accompanied by ten of her family members. Cronauer acknowledges Trinh’s reticence, and promises he has no expectations for their relationship. Former Vice President Richard Nixon visits Vietnam, and gives a speech in which he states confidently that the Viet Cong will be defeated. A recording of the speech is to be aired on Radio Saigon. Cronauer sabotages it by inserting his voice as if he interviewed Nixon, making jokes about Nixon’s sex life and marijuana use. Hauk panics when he hears the broadcast. He wants to fire Cronauer, but Gen. Taylor forbids him, arguing that he is their first deejay to receive fan mail. Later, Tuan finds the deejay at Jimmy Wah’s, and insists Trinh wants to see him that instant. The boy lures him out of the bar seconds before it is blown up. In the aftermath, Tuan disappears. At the radio station, Sgt. Maj. Dickerson forbids Cronauer from reporting the blast, but the deejay ignores him and mentions it anyway. Dickerson demands that he be punished, and Taylor agrees to suspend him. Lt. Hauk takes over Cronauer’s slot. He makes bad jokes and plays polka records, eliciting a flood of complaints from servicemen who want Cronauer reinstated. Meanwhile, Tuan brings Cronauer to his village, where they observe Buddhists praying for enlightenment. Trinh pulls him aside to tell him they have no future together, and cannot be friends. Later, Garlick finds Cronauer at a restaurant with Tuan, and tells him he has his job back. Cronauer refuses to go, and asks Garlick to drive him to his English class, instead. On the way there, stuck in traffic, they find themselves surrounded by soldiers in trucks. Garlick announces that Cronauer is with him, and the soldiers cajole him into an impromptu live broadcast. Reminded that his purpose is to entertain troops whose lives are in danger, Cronauer returns to work. He asks to interview soldiers in the field, stationed in An Lac. Dickerson learns that the road to An Lac is under Viet Cong control, but conceals that fact. He approves the trip, knowingly endangering Cronauer and Garlick, who drive over a land mine in Viet Cong territory. Tuan gets word that Cronauer is in trouble and goes to rescue him. When he is safely returned to the radio station, Dickerson informs him that Tuan is a Viet Cong operative, and orders Cronauer honorably discharged. In town, Cronauer finds Tuan and accuses him of being “the enemy.” Tuan insists that the U.S. is the real enemy, and is brought to tears as he reveals that his mother and brother were killed by American soldiers. The next morning, Garlick escorts Cronauer to the air base. On the way, the deejay asks to stop in town. He gathers his English students and organizes a game of baseball, using sticks for bats and pieces of fruit as baseballs. Afterward, he says goodbye to Trinh, who thanks him for his kindness. Before he boards the airplane, Cronauer gives Garlick a farewell tape to air on Radio Saigon. Garlick takes over Cronauer’s slot, and plays the tape as his first broadcast. It begins with the beloved deejay bellowing, “Goodbye, Vietnam!” He performs a fake interview with one of his characters, “Mr. Leo,” to tell the American troops that he is headed home.