London, 1914. The explorer Ernest Shackleton attempts to raise funds for his expedition to the South Pole on the eve of the First World War, as well as struggling with a complex personal life and his brother's imprisonment for fraud.

With their ship trapped, Shackleton and his men are forced onto the ice, and it becomes clear that the only way out is to haul boats across the ice floes to the sea. Against all odds, the men reach the water and endure a ninety-mile journey across the South Atlantic to Elephant Island.