(plaintive flute music) - Inside the once majestic country of Cambodia, after a decade of war, history witnessed the collapse of the horrific Khmer Rouge regime.

It would end one of the worst genocides the world has ever seen.

(taut piano music) This memorial helps to ensure that the world never forgets those who died during the years of Cambodia's killing fields.

(mellow piano music) Yet there's more to the story, there is the untold episode of the fate of thousands of these survivors who sought refuge inside Thailand.

(mellow piano music) This is my father, Bunseng Taing, in a refugee camp in 1980.

I knew since my childhood that my father was a survivor of the killing fields, but I was shocked to learn that he and many thousands of others faced a more terrifying atrocity, the massacre on the Temple Mountain called Preah Vihear.

My son, James, he never give up.

He always push me to tell him the story.

And I always say to him, I said, "I don't want to relive again, just don't, you know."

So he just say, "Well, just just tell me one time."

So that is how we get here to do the documentary.

(pensive music) (somber music) (bird screeching) When I was a child, I never thought that I would leave the country.

I was the youngest of eight children.

My family was very close.

My dream was have a piece of land, build my own house with a pond, and raise my own animals, and have lots of kids.

(dreamy music) The market in Cambodia was full of good food.

No one was starving before the war.

(vehicle engines roaring) My childhood, we were living outside of Phnom Penh.

Phnom Penh was a very modern city.

(dreamy music) - Growing up in Phnom Penh, I lived somewhat of a Western life, with refrigerator and TV.

- [James] Though Thida Buth Mam and my father met only recently, her story parallels his in many ways.

(mellow music) - At that time, TV was turning from black and white to color, and rock and roll came in.

So, I was exposed to the English language at a very early age.

And then the war came in, and the war really stopped life for me.

- In cooperation with the Armed Forces of South Vietnam, attacks are being launched this week to clean out major enemy sanctuaries on the Cambodian Vietnam border.

This is not an invasion of Cambodia.

(plane engines whining) (bombs exploding) - [James] This began years of intense bombing campaigns.

From 1970 to 1973, the United States dropped more bombs in Cambodia's heartland than were dropped in Japan during the Second World War.

It was equivalent to five Hiroshimas.

- [Bunseng] To escape from the bombing, my family fled west to the countryside near the Thai border.

- [James] The American bombing caused enormous instability, enabling the communist Khmer Rouge, once a small faction, to gain power.

Its leader, Pol Pot, envisioned an agrarian revolution.

(crowd chanting) (guns exploding) (engines roaring) It aimed to wipe out everything he determined to be modern.

(people clamoring) When the country fell to the Khmer Rouge in 1975, its army purged the cities and committed atrocities on an unbelievable scale.

(guns firing) (indistinct chattering) - When we were forced out of Phnom Penh, my father told me, "Everything is gonna be okay."

And that's the last time I remember my father.

(indistinct chattering) - [James] Seven million people were forced into labor camps.

(men grunting) When my father got sick, I tried to go and go to visit him.

And I got captured by the Khmer Rouge and I was tortured for 40 days.

- It is all mass killing, and they take all our food, so we were starving.

No medical care, so people were just dying from all that.

- [James] Between 1975 and 1979, 1/3 of Cambodia's population was either executed or tortured and starved to death.

The genocide would become known as the Killing Fields.

(ominous music) - The Khmer Rouge were killing off all the people from the city, and was coming close to my village, and they stopped.

The reason was there was a coup d'etat in Phnom Penh.

- [James] On Christmas day, 1978, communist Vietnamese troops invaded Phnom Penh, forcing Pol Pot out of power.

(truck engines roaring) In the chaos that followed, forsaking and starving Cambodians fled to the border with neighboring Thailand.

(engines roaring) - [Thida] We have to make the escape because the chance of surviving in another communist regime is very low for all of us.

- After the concentration camp, I reunited with my father and my father told me that we have to get out the country right away because we don't know the situation of the country, we have to get out now.

- We make an ox cart (laughs).

We make our own wheel from scratch.

We prepare this for a three-month journey.

(wheels clacking) - [James] As refugees began to mass on the border of Thailand, a group of frontline international aid workers scrambled to help.

(chattering in foreign language) - We were disappointed there wasn't more public outcry.

I mean, this was a major human rights violation.

(indistinct chattering) With just us trying to whip the Western press into some attention on this, the Thai press covered it, if at all, barely.

- [James] After this period, the Thai government worried the Vietnamese agents would penetrate their borders.

Without adequate assistance to manage the stampede, they were reluctant to allow refugees across into Thailand.

- The US was, and it was sitting empty-handed.

You know, well, we didn't have a large refugee program.

- [James] Lionel sought help from Macalan Thompson, who had been working with refugees from Laos and Vietnam.

- [Macalan] The spring of 1979, you know, sort of doubled up the problems on the Thai government, with all these very large numbers of people coming in, illegal aliens, and essentially starving.

It'll look like people, you know, coming right out of Auschwitz.

What are they going to do with them?

Skin and bones many of them, and many died on the way.

- [James] By the time my father made it to the border, the Thai government had agreed to allow some survivors to be brought into makeshift border camps.

- We escaped that day with thousands of people that poured into the border.

(children laughing) And I remember before they put us in the camp, they bring the trucks to the border and help us get on the trucks.

And the truck drove through the city of Aranyaprethet.

And it's the first time that we saw electricity and we are so happy we all threw our fist up to the air.

It's freedom, it's freedom, it's freedom.

- [Thida] And we couldn't believe our luck.

Our spirit was high, we were hopeful.

I mean, we have been cut off from the world for four and a half years.

- So, we make it to the refugee camp.

(mellow flute music) Surrounding it a barbed wire.

(mellow flute music) But one of the best times that I had with my family.

We feel that we're not being killed or starving again.

And every day we enjoy every moment at the refugee camp there.

We playing music.

We talk to friend.

We talk about the past and about the new future.

(somber music) - [James] By June of 1979, the Thai government became impatient with the pace of Western action, and threatened to force refugees back into Cambodia.

- As the population along the border grew, the Thai became increasingly apprehensive.

- None of us could get round the fact that this was becoming a very inconvenient problem for our political masters.

It was, you know, showing no signs of abating.

The numbers are massing on the border in the border camps.

- Very rapidly, when it became evident that this was gonna be a major humanitarian disaster, people came forward and were mobilized very quickly, but it was not a pretty sight.

(truck engines roaring) - There was resettlement going on.

Buses would come, people would leave, but even then you weren't sure they'd be processed.

You didn't know where they would go or what would become of them.

And for most of the people, they didn't know if they were gonna get resettled.

They lived with constant anxiety over this.

And we also didn't know.

In fact, we were being told that everybody was gonna be pushed back to Cambodia, you know, any day now.

(indistinct chattering) - We were out there constantly, trying to identify those closest to the US and send them off to other camps away from the border.

- [James] My father's happy interlude in the border camp were short-lived.

- [James] One day, rescue workers arrive with buses, and began calling out names.

(chattering in foreign language) (speaks in foreign language) (bus engine roaring) - June 12 or 13 early in the morning, I remember the bus arrived at alongside refugee camp, and the Western people came with microphone on their hand and they call people by name to get on the buses.

(indistinct chattering) - The scene was just tension-filled from the time we arrived that morning.

(bus engine roars) - And they keep calling, and then more and more people get in the bus.

(people clamoring) - Refugees were surging towards the front of this enclosure.

- And I keep waiting for my name being called.

- [Lionel] And we would try to call out the names, but it was very chaotic.

We only had about three hours to do this.

By midday, we were told we had to finish.

In fact, several times, the Thai would say, "You're done."

We'd say, "No, we just need a few more minutes."

(horn honking) - The Thai soldier came down and shut them down and pushed them out of the refugee camp, not allow them to call the name anymore and they closed the gate.

(vehicle engine roaring) - [James] After permitting the relief workers to relocate just a few thousand refugees, Thai soldiers cut off the rescue and forced a desperate mob, my father among them, back into the camp.

(vehicle engine roaring) - The next day, we heard a rumor that those people being forced back to the border.

- They told us "You're going to Bangkok, to a refugee camp in Bangkok."

So there's this mixed feeling of fear and happiness, we don't know.

(tank engine roaring) - We knew something was going on.

All these buses were carrying refugees away from the camps somewhere we didn't know where.

- We told them that if you send us back, we gonna be get killed by the Khmer Rouge.

We just ran to the corner, crying, beg them not to send us back.

About 2,000 us, children and old, we are human-chained to each order, that we refuse to get on the bus.

We won't get on the bus, doesn't matter what.

Even if they will kill us, we gonna be dying here.

They grabbed the little baby and the children out of their mothers' arm and threw them on the buses.

So, when their children got on the buses, the parent automatically get on the buses.

And they kicked us.

They beat us up.

We had no choice but to get the buses.

(man speaks on megaphone in foreign language) - I saw some people that they put their hand up to here, that you're being killed, you know.

And I saw a couple Westerners and they are crying and crying.

They tried to help us, but they've no way to get to help us.

We were terrified inside the bus because we don't know where they're taking us.

And we still have hope that they maybe tell us the truth that they transfer us to a different camp.

(bus engine roaring) The bus drove us 14 hour, 14 hours that night until early in the morning.

- [Lionel] What happened was they had about several tens of thousands of refugees scattered in various camps along the Cambodian Thai border, and the Thai government, for some reason, decided that it was going to push these people back to Cambodia.

They were tired of them, whatever.

They gathered together about 42,000 of them, took 'em to this temple on top of a mountain on the border called Preah Vihear, and pushed them down the cliff.

(ominous music) - [Bunseng] And when we got there, we don't know where we are, and they forced us out from the bus at gun point and they told us where to go.

And we found out that we are on top of the mountain called Preah Vihear Mountain.

- [James] Almost four decades later, I accompany my father and my uncle to visit what remains at the site of the Preah Vihear Massacre.

- It's very difficult to walk through here.

We follow the track that everybody went.

On the top of the mountain, the Thai soldiers told us that whatever we have, water, monies, gold, valuables, just give it to them.

And they say, "You're not gonna need it down there."

Just drop it in the bucket and give it to them.

And you can see the cliff is so steep down.

And they keep gunning us down.

We had no way to get down.

We had to hold, (sobs) hold a vine to lower ourselves down, (sobbing) cliff by cliff.

(speaks in foreign language) - [Translator] When we helped the old people, they fell down.

They crashed into the branches.

In agony, they dropped all the things they carried with them, and they abandoned a lot of their belongings there.

That night, every five minutes we heard boom.

(gun fires) And everyone was crying.

People appeared with blood all over their body, some of their eyeballs falling out, broken skulls, screaming, looking for their mother and father.

- You know, I lived through the Khmer Rouge.

I thought that was bad, but that night was the worst night of my life.

(mimics machine gun fire) And I hear the bullet go through my ear, like (swooshing) right behind from my ears.

And I saw a little girl in front of me, the bullet hit her head and she collapsed.

I hold onto my mom's hand.

And my thought was, at least we die together as a family.

They want us to walk on those landmine, and then very few survive.

And it would make a good lesson that we will never come back to Thailand.

They want to kill as many refugee as they can.

So, walking 40,000 refugee through the deepest mountain, with no water and with gun behind us, that's one way to kill people.

And they don't have to open fire because the landmine will do the job.

- The brush is so thick.

(plane whirring) We heard the planes, the sound of planes flying through.

(sniffles) We thought someone come to help us.

43,000 refugee cry out, (sniffling) for help (sobbing).

But no one come for us (sobs).

The soldiers say there are lots of bodies down in that area where they can't bring us.

- [Bunseng] And the landmines still there.

That's why we can't get in there.

- [James] So we've been finding more and more of the stuff.

And the ground here, the clothes, the plates that we just saw, and then they pick up a few bones here and there.

- This is a bone that one of the refugees that die here.

- [Bunseng] This might be a blanket, you know.

For the UN gave it to us.

Sometimes we used that to cover the body because the body is all here.

Wrap the body and just let it sit and rot it.

(speaks in foreign language) - [Translator] The strong men that carried rice and carried supplies, ran to seek water to cook rice and other things.

Then the landmines exploded.

And when it exploded, they all died.

And the people that didn't have food ran to grab the bloody rice off of the dead bodies, just to have something to eat.

They had to wash the blood off the rice and cook it.

- Thousands of refugee passed through here, 13,000 lost their lives.

This is all they left behind.

(sobbing) I lived through Pol Pot for almost four years.

I was detained, put in a concentrate camp, tortured.

But To live through Preah Vihear for that three months time is worse, worse than you could even imagine.

For 30 something year, I still have a nightmare, night after night.

My father and I walked through the jungle for three months.

When we got on a small city, I found my brother, Chiv, and we settled down.

And my father keep telling me that you have to leave and go back and escape again.

I said, "How could I escape again, I mean, after all we lived through and been through?"

My father said, "You're still young.

You still have opportunity.

It's not safe to be here."

And I say, "What about you?"

He said, "Just leave."

So, I was very upset when he want me to leave him.

And I left him without, (sobs) without saying goodbye to him.

(melancholic music) Well, we escaped back into Thailand three months later.

Fortunately this time, I got rescued.

(melancholic music) The Western person that come and rescued me, put me in a minivan.

And when the minivan drove away from the campsite, I broke down.

I never cried hard in my life, that I was safe.

And a month later, I received a letter from my brother that my father passed away (sobs).

- This time, they took me to a legal refugee camp called Buriram.

(laughing) And when we reached Buriram, we celebrate, because now we are legal refugee.

And to me, that was a gift.

To me, that was a second life.

So, I made it.

(birds chirping) (metal clanking) - [Bunseng] Today, I'm a painter.

I have more than I can imagine.

And I kind of like to become a painter because I able to travel to different places, meet different people.

One thing that I wished for for many years was to be able to say thank you to the people who saved me.

I did not know their name.

- [James] One day while painting a house, that wish came true.

And the seed for this film was sown.

It turned out that the homeowner was renovating the house for his stepfather, Bob Devecchi.

- Doug came into the room, and introduced me to Bunseng.

- And I'm shaking (laughs).

I said, that's the man that I'm looking for for all these years.

I meet my hero.

(both laugh) (plaintive flute music) (melancholic music) - I was remembering feeling so sad that all I had was this plastic bag full of scraps of paper with names and pleas for help.

If we'd known they were being sent back to a minefield, we probably would've stepped in front of the buses or something, but a terribly brutal, tragic thing to have done.

And it was only later that we began to realize from people who had not gone down, that they heard the cries of others, or few people actually made it from the minefields back up the cliffs.

And we began to learn as we got permission to rescue survivors that this tragic event had occurred.

- Before you go- - Yeah.

- [Bunseng] Just want to show you the picture.

- Oh.

- This is a two family that you saved from the mountain.

- That means a lot to me.

- Yeah.

So, I like to thank myself, in behalf of them, and a lot of people that, people like you.

- Thank you.

Thank you.

It makes my life very happy to know that you still remember, to know what we did.

This is the kind of concrete example that we never had time to appreciate during that time.

And I only came because I knew your story from James.