Aluna is a 2012 feature-length documentary film sequel to the 1990 BBC documentary From the Heart of The World: Elder Brother's Warning. The first documentary showed an ancient Kogi tribe civilisation (the Elder Brother) who emerge to offer their concern for people of the modern world (Younger Brother). Younger Brother is urged to change or suffer environmental disaster. After offering the warning, the Kogi retreat to their community hidden in the mountains of the Sierra Nevada de Santa Marta, Colombia. In the second documentary, the Kogis have re-emerged, realising that the importance of their warning was not grasped. As well as warning Younger Brother, they have decided to share their understandings of how nature works in the belief that doing so will share their burden of healing the dying planet. Content summary Realising that their warning in 1990 was not fully grasped, the Kogis become more proactive. Even though their civilisation has never used wheels or created writing, they diligently study film cameras and train their own indigenous film crew. The Kogis ask Alan Ereira, whom they allowed to film their 1990 message, to assist. The Kogi Mamos decide that there will be "no more secrets": They want to demonstrate their planetary healing sciences in front of the cameras to the modern world and show visible and measurable results. They also wish to teach other people how to conduct these sciences in order to heal the world. They speak with modern scientists in the belief that they have a different science to show them. Kogi demonstration To help convince the modern world of the importance preserving the planet, the Kogi demonstrate its interconnectivity. A small group of Kogis travel to London to fetch 400 kilometres (250 miles) of gold thread, reportedly the longest ever made. Mama Shibulata, one of the Kogis Mamos in the group, visits the observatory at the University of London where he meets Richard Ellis, the Steele Professor of Astronomy. Ellis is astounded by Shibulata's knowledge of both the Solar System and astronomical discoveries such as dark energy. After their return to Colombia with the gold thread, the Kogis conduct the demonstration. A group of leading modern scientists observe the results and find that the science of the Mamos may be at the 'cutting edge' "They lay the gold thread from one river estuary in Colombia to another in order to show how the destruction of river