Filming.
Exterior shooting began on the island of Luzon in the Philippines in February 1986, although the production was almost canceled because of the political upheaval in the country, due to then-president Ferdinand Marcos. With the help of well-known Asian producer Mark Hill, the shoot commenced, as scheduled, two days after Marcos fled the country. Shooting lasted 54 days and cost $6.5 million. The production made a deal with the Philippine military for the use of military equipment. Filming was done chronologically. Upon arrival in the Philippines, the cast was sent on an intensive training course, during which they had to dig foxholes and were subjected to forced marches and nighttime “ambushes,” which used special-effects explosions. Led by Vietnam War veteran Dale Dye, training put the principal actors—including Sheen, Dafoe, Depp and Whitaker—through an immersive 30-day military-style training regimen. They limited how much food and water they could drink and eat and when the actors slept, fired blanks to keep the tired actors awake. Dye also had a small role as Captain Harris. Stone said that he was trying to break them down, “to mess with their heads so we could get that dog-tired, don’t give a damn attitude, the anger, the irritation … the casual approach to death”.