Eight celebrities embark on a 12-day expedition in the rainforest of Costa Rica, where they must learn to navigate difficult terrain, build shelters, make fire and eat the food that nature provides. From abseiling down ferocious waterfalls to crossing perilous rapids, the stars face a range of challenges and Bear himself eliminates one of them each week, leaving three in the final.

In this series, naturalist Chris Packham reveals the natural world in a way that you’ve never seen it before. For him, what is really beautiful about nature is not the amazing animals and plants that we share the planet with but the hidden relationships between them. These relationships may sound bizarre but without them, no life would be possible. Discover previously unknown relationships, like why a tiger needs a crab; or why a gecko needs a giraffe. Each week Chris visits one of our planet's most vital and spectacular habitats and dissects it, to reveal the secrets of how our living planet works.