With the help of a fellow soldier Huan (Ben Rindner) he starts translating the diary, which belonged to Dang Thuy Tram (Minh Houng), a doctor who was positioned at the field hospital for several years.
She describes in vivid detail the horrors she experienced during the war: her friends die around her every day, food is scarce, and she misses her family.
Once Fred returns to the United States, his translation efforts continue with the help of his brother Robert Whitehurst's (Brian Townes) Vietnamese wife Mai (Tina Duong).
While the family's long history of military service in the US army initially clashes with the empathetic writing of their supposed enemy, they eventually grow to be inspired by Thuy's altruism.
When asked what had impressed Fred most about the diary, he claimed it was the passage "Và ai có biết chăng ai/ Tình thương đã chắp cánh dài cho ta…" which translates to "And do you know/ Love has given us wings..." Returning to Hanoi, he began to write the script for the film, which was initially called "there is fire in this".