As he enters Korowai territory for the first time, Will Millard discovers that many of the Korowai who are still living 'traditional' lives have become used to being visited by tourists and filmed for other TV documentaries. They have become skilled at selling a version of their culture to foreigners, delivering what they think people expect to see. But then Will hears about two old men, White Beard and his brother, who are apparently still living in a treehouse in the depths of the forest. Will can't pass up this opportunity to find out if anything still remains of the traditional Korowai way of life.

Will returns for his second trip to the Korowai to spend more time with Haup (White Beard) and Halap. They are some of the last remaining Korowai still living permanently in a treehouse without any real contact with the outside world. When Will first meets them, their adopted son August is there with them in the forest and his wife Amel gives birth one night, cutting her own umbilical cord with a sharpened piece of wood. But it soon turns out that they spend most of their time in the government-sponsored villages six hours walk away, and have decided to come to the treehouse to see if they can work with the film crew. So Will asks them to return to their government-built village, preparing to spend 10 days living with Haup and Halap alone in the middle of the forest.

Will returns for his final two trips to Korowai territory, to try and find August and his family. He is keen to spend time with them too, to better understand how most Korowai live today. But when he gets to their village, they are nowhere to be found - apparently they have gone to a 'grub fest' two days walk away in the forest. These extraordinary events only occur every couple of years, so Will decides to head there to see if he can find them. He arrives at the start of a massive festival of 'sago grubs', where sago grubs are backed on hot stones into a kind of pizza and shared with Korowai from all over their territory. Approximately ten per cent of the entire Korowai population have turned up with bows and arrows to dance the night away and feast on sago grubs. But when Will and August return to his village, the pressures facing a community in transition boil over, and Will finds himself in the middle of a very dangerous situation.