In the middle of the Indian Ocean, more than 1.500 km from the nearest continent, lies an untouched, mysterious archipelago – the Chagos Islands. This group of 60 islands is one of the last pristine wildernesses on Earth. The Chagos Archipelago is one of the world’s largest marine national parks, and is strictly protected. A scientific expedition has been granted access to this politically disputed territory for the first time. In times of climate change, as global reef communities face a growing crisis, the researchers seek to show how coral reefs fare in places with minimal human interference. During a journey into the unknown, we follow in the footsteps of internationally renowned scientists, who aim to unlock the secrets of a lost world and gain astonishing insights into one of the last true wildernesses on Earth.