When you picture a 1921 Arctic expedition, you imagine hardened bearded men. Yet the only human to survive the crushing isolation of Wrangel Island was a 23-year-old Inupiaq mother with no wilderness training, armed with a sewing kit and a desperate desire to save her sick son. This episode reconstructs the harrowing true story of Ada Blackjack.

Recruited as an English-speaking seamstress for a doomed expedition built on Vilhjalmur Stefansson's friendly Arctic theory, Ada was left alone after three men vanished on the ice and a fourth died of scurvy. Over eight months she taught herself to hunt, trap, and build a boat, surviving through methodical intelligence and fierce devotion.

• She once walked 40 miles across Alaska with her son Bennett after being abandoned by an abusive husband
• She joined the expedition to earn money ...