A thousand years ago the Khmer people of Cambodia built an empire that stretched a million square kilometers. It became the largest superpower the region has ever seen. Their capital was the great city of Angkor, once the largest city on Earth. Its centerpiece was Angkor Wat - a vast temple complex covering an area more than four times the size of Vatican City

Buried in the Cambodian jungle lie the lost remains of the great medieval city of Angkor, once the capital of one of the world\\\'s greatest civilisations. Today, only the great stone temples like Angkor Wat survive. But Angkor was once a teeming metropolis, full of life - the biggest city on Earth.

The Khmer Rouge slaughtered nearly two million people in the late 1970s. Yet the Killing Fields of Cambodia remain unexplained. Investigative journalist Thet Sambath records shocking testimonies, from the foot soldiers to Pol Pot's right-hand man.

Unreported World reveals how 30 years on from the fall of the Khmer Rouge, and at the same time as Pol Pot's accomplices are being put on trial for war crimes, Cambodia's people are once again being brutally driven from their land. This time, however, it is capitalism, not communism, that is displacing them - as growing numbers of tourists fuel a property boom that is having devastating results.

40 years ago, sisters Hong and Bo were separated by a brutal war. They've been looking for each other ever since. Watch the moment they meet.