In a real-life detective story, Chris Packham return to Sumatra in Indonesia to search for a girl he photographed 20 years ago and discover what’s happened to her rainforest home.

In 1998 wildlife enthusiast and keen photographer Chris Packham had a remarkable encounter with the Orang Rimba, a tribe of hunter gatherers in the rainforests of Sumatra, Indonesia. It was the first time he’d ever seen people living in perfect harmony with their environment.

One photo Chris took, of a young tribal girl, has since become immensely important to him as a barometer of the condition of the planet. In this real-life detective story, with no clues as to her identity or whereabouts other than his original photograph, Chris sets off to Sumatra to try and find her: the lost girl in the picture.

Chris’s search is further complicated because her tribe is nomadic, often covering vast distances on foot. Since he was last there, millions of hectares of her rainforest habitat has been destroyed. Piecing together the clues, Chris discovers to his horror that the girl’s close knit group of Orang Rimba was attacked not long after he met them, and a number of them killed. But was the girl among them?

Travelling into the heart of Sumatra Chris discovers just how much of Sumatra’s once pristine rainforests have been replaced by palm oil plantations. With palm oil used in around 50 percent of the products we buy in our supermarkets, Chris learns some uncomfortable truths about how we are all in some way connected to deforestation.

As Chris’s investigation reaches its dramatic conclusion, will he find the girl alive? And if so, will she still be living in harmony with nature, as she was 20 years ago?

Chris Packham: In Search Of The Lost Girl goes out at 9pm, Sunday 28 January on BBC Two.

It is a Tigress Production for BBC Two. The Executive Producer for Tigress is Sarah Swingler; the Producer/Director is Dominick French. The BBC Commissioning Editor is Abigail Priddle.