O’Brien recalls a story of Rat Kiley’s. Though Rat swears the story is true, O’Brien doubts its accuracy. He explains that Rat exaggerates not because he wants to deceive, but because he wants listeners to almost feel the story so that it seems more real. Rat had been assigned to a medical detachment near Tra Bong in an area the medics shared with six Green Berets. The groups did not interact often. During an all-night drinking session, a medic jokingly mentions that the medics should pool their money and import some prostitutes from Saigon. One medic, Mark Fossie, is taken by the idea, and six weeks later his high school sweetheart, Mary Anne Bell, arrives at the compound.
Young and naïve, Mary Anne insists on learning about Vietnamese culture and the Vietnam War up close. She assists when the medical unit receives casualties. Eventually she stops wearing make-up, and her attention is consumed by learning how to use an M-16 assault rifle. Fossie suggests that she return home, but she does not. She begins staying out late, finally staying out all night. Fossie, realizing Mary Anne is missing, wakes up Rat. They search for her but do not find her.
O’Brien interrupts the story to comment on how Rat told the story. Rat would stop with Mary Anne's disappearance and ask where she might be. Mitchell Sanders guesses that she was with the Green Berets because Rat mentioned them, and that is how stories work. Rat would resume the story and tell his listeners that she was resting with the Green Berets in their hootch after an all-night ambush.
The next morning Mary Anne returns wearing green fatigues and carrying a rifle. She tells Fossie that they will talk later, but he is angry and will not wait. Later that day, Mary Anne appears fully groomed, wearing her feminine clothes. Fossie explains that they officially became engaged, and the pair maintains a façade of happiness. Fossie makes arrangements for Mary Anne's trip home. The next morning she disappears again with the Green Berets. Three weeks pass until she returns. The next day Fossie waits outside the Green Berets' area, waiting to see Mary Anne. He hears an eerie human voice. Pushing inside the Green Berets' hootch, he sees piles of bones, smells a horrendous stench, and hears Mary Anne chanting. She tells Fossie that she likes this life and that he does not belong there.
Rat's platoon buddies dislike the abrupt ending and ask what happened to Mary Anne. He tells them that the rest is hearsay, but that he understands that she disappeared into the jungle.
