Danger Close: The Battle of Long Tan is based on a true story. It depicts the real-life Battle of Long Tan, which took place during the Vietnam War on 18 August 1966 in South Vietnam.
On 18 August 1966, Australian and New Zealand soldiers fought against a much larger Vietnamese force in a rubber plantation near Long Tan.
- The Australian force: D Company, 6th Battalion, Royal Australian Regiment, consisting of approximately 108 men.
- The commander: Major Harry Smith, portrayed by Travis Fimmel.
- The battle: The soldiers fought for approximately three and a half hours in heavy rain while facing enemy attacks and running low on ammunition.
- The outcome: The Australian troops held their position with support from artillery, reinforcements and armoured personnel carriers.
- The casualties: 18 Australian soldiers were killed, while the number of Vietnamese casualties remains disputed.