In the first episode, Prof Iain Stewart explores the relationship between the deep Earth and the development of human civilisation. He visits an extraordinary crystal cave in Mexico, drops down a hole in the Iranian desert and crawls through seven-thousand-year-old tunnels in Israel to find out just how the Earth bubbles and shifts beneath our very feet.
His exploration reveals that throughout history, our ancestors were strangely drawn to fault lines, areas that connect the surface with the deep interior of the planet. These fault lines gave access to important resources, but also brought with them great danger; raising impassible mountain ranges, forming devastating volcanoes and providing catastrophic earthquakes.
With spectacular images and surprising stories, the series discovers the central role played in our history by four different planetary forces.