Haing S. Ngor won an Oscar from his only nomination for portraying Dith Pran in The Killing Fields.
For the first half of the film Ngor really is supporting to Waterson who portrays journalist Sydney Schanberg. Dith Pran acts as an assistant and interpreter to Schanberg. First this first half Ngor acts as another empathetic human face on the situations he goes through. Ngor's quiet reactions to the horrors he sees, and the danger he predicts, are completely authentic, and very effective.
Ngor along with Waterson do something rather fantastic, and that is develop a friendship between the two characters despite the fact the film spends very little time with this very important aspect of the film. They develop a quiet but incredibly endearing friendship between these two men, never really with any dialogue, but it is clearly there between the two that incredibly handled by both actors.
In the first half Ngor has two key scenes, in which his honest authentic quality of performance makes these scene all the more powerful. The first scene is when he pleads with Khmer Rouge soldiers for the lives of his journalist friends. It is a very simple scene in terms of Ngor's performance in terms of his quiet pleading. Ngor makes this scene completely believable in the way it turns out due to Ngor's quiet but incredibly effective performance. Another incredible heartbreaking moment is when all the other journalists say goodbye him. A simple but incredible scene due Ngor's pure honesty.
The second half of the film does become almost completely about Dith Pran trying to survive in Khmer Rouge controlled Cambodia, making Ngor the lead in this second half. Ngor's performance is almost completely silent in his performance with only a narration telling of his thoughts. Pran must play dumb since all people with foreign ties, or intellectual backgrounds are killed. Ngor's performance is very careful, but simply outstanding as we follow him through his trials. He puts a true human face on these events which is essential to the film.
Pran makes an escape in attempt to get away from the mass killings, as he does his best to not being figured out, accidentally stumbles on the massive killing fields, and faces a dangerous journey across Cambodia for safety. Ngor's performance stays almost silent but outstanding because he still channels completely what Pran is going through. Ngor's performance is simple just a purely authentic, incredibly subtle, and brilliant performance.