Hollywood

“Pol Pot was still mounting an insurgency in Cambodia (after Vietnam had overthrown the Khmer Rouge) when the film was being made in neighboring Thailand. In fact, the Thai authorities were very keen to have the horrors of Pol Pot's regime depicted onscreen as it would bring international attention to the political situation there.”

“Haing S. Ngor originally didn't want to have any acting involvement in the film as it was all a bit too raw for him. However, Roland Joffe simply couldn't find another Cambodian actor for the role, mainly because one of the Khmer Rouge's policies was to kill all actors.”

“Haing S. Ngor had to flee the set after re-enacting the harrowing scene where he is faced down by a female teenage soldier as it evoked too many horrific memories of his time spent living under the Khmer Rouge regime.”

(IMDB page with lots of trivia facts)
http://www.imdb.com/title/tt0087553/trivia

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