Beneath our feet is a world wide web that keeps us all alive. Estimated to be the origin of about 97% of the calories we eat, soil is fundamental to life. But it's a whole living world of its own. A biological engine, a carbon sink, and home to an abundance of bacteria, insects and worms. Tom Heap and Helen Czerski find out how soil is made, how it's faring in a world of intensive farming and how to get it back to full health. Joining Tom and Helen to dig into the hidden drama of soil are:Jack Hannam, Professor of Sustainable Agriculture &amp; Biodiversity at the University of Greenwich’s Natural Resources Institute
Duncan Farrington MBE, farmer and founder of Farrington Oils
Simon Jeffery, Professor of Soil Ecology at Harper Adams University
Dr Rachel Cassidy, lead scientist on Northern Ireland's Soil Nutrient Health Scheme.
Andrew Baker, Soil Acoustics.Producer: Beth Sagar-FentonAssistant Producers: Rebecca Rooney and Toby FieldRare Earth is produced in association with the Open University.

Environmental journalist Tom Heap and physicist Helen Czerski tackle major stories about our environment and wildlife, celebrate the wonder of nature and meet the people determined to keep it wonderful.