In 1914, former US President Theodore Roosevelt nearly died in the Amazon. Feverish and delirious from an infected wound, he asked his son to leave him behind — and carried a lethal dose of morphine in case the end came.

Roosevelt had gone to Brazil after losing the 1912 election, the strongest third-party run in American history. A planned speaking tour turned into an expedition to chart the River of Doubt, an uncharted Amazon tributary, alongside the Brazilian explorer Cândido Rondon. It went badly wrong: wrong boats, a drowned crew member, a murder among the men, malaria, starvation, and the leg injury that nearly killed Roosevelt before they reached safety.

Dr Michael Cullinane, Walton Chair of Theodore Roosevelt Studies, joins Hugh to tell the full story — what happened on the river, how Roosevelt survived it, and why a man who h ...