Episode 1

The launch of the BBC's ambitious seven-year natural history project, in which six presenters visit six of the planet's most threatened ecosystems to meet the people fighting to restore the Earth's delicate balance.

In this first episode, Steve Backshall, Chris Packham and Ella Al-Shamahi visit the Maldives, Iceland and Cambodia.

Steve Backshall travels to the Maldives, an area facing significant challenges because of climate change. Warming seas and the acidification of the oceans have led to coral bleaching on a massive scale, destroying the surrounding ecosystem. The biodiversity of the reefs provides food security, income and other benefits to the people of the Maldives, and Steve finds that they are working hard to try to stem the tide of destruction. He also goes diving off the reefs to check on a group of manta rays, whose presence offers a clear indication of the health of the reef.

In Iceland, Chris Packham learns more about the effects of global warming. Temperatures in the Arctic are rising at more than twice the annual global average. Snow and ice are melting at an increasing rate, which contributes to rising sea levels and is likely to provoke extreme temperature events beyond the Arctic. As one of the eight Arctic States, Iceland is being dramatically affected by rising temperatures, with the lives and livelihoods of many islanders being threatened. Chris also discovers that melting sea ice is opening the Arctic to navigation. These seas are home to many species of whales, so Chris joins a team of young scientists monitoring the impact of increased commercial shipping on humpback whales.

On the other side of the world, Ella Al-Shamahi visits Cambodia in Southeast Asia, an area experiencing increasing economic growth. However, growth is putting massive pressure on natural resources, with ever-expanding cities and devastating overexploitation of the natural world. The Mekong river is the lifeblood of this region, but whole sections of it are under pressure. Ella meets a fishing community living on the Tonle Sap lake. The lake used to offer rich fishing grounds for local communities, but the construction of many dams along the wider Mekong is now threatening to destroy the biodiversity of this once abundant lake.

The building of new roads has given poachers easier access to forests, and the illegal wildlife trade is big international business. Ella visits a project in Cambodia that rescues and rehabilitates illegally trafficked wildlife, including pangolins, the most trafficked mammal on Earth.