There are six crucial substances in human history: sand, iron, salt, oil, copper and lithium. They took us from the Dark Ages to the present day. They build our homes and offices, power our computers and phones, and create life-saving medicines. But most of us take them completely for granted.

In his search for the origins of these vital substances, Sky News Economics Editor Ed Conway has travelled the globe – from the sweltering darkness of the deepest copper mine in Europe to the eerie green pools where lithium originates – to uncover a secret world we rarely see. In June 2023 he came to Intelligence Squared to tell their story and the little-known companies that turn raw materials into products of astonishing complexity.

As we wrestle with climate change, energy crises and the threat of new global conflict, Conway argues that we need a greater understanding of the substances that underpin our lives.