In 2015, climber Tommy Caldwell took on the hardest challenge of his life, spending 19 days freeclimbing Yosemite's vertical, 3000-foot Dawn Wall - regarded as the most difficult climb in history and a route nobody had ever done before.
This odds-defying feat was the culmination of seven years planning and a lifetime of determination.
Here, he recounts how he got there, the falls and setbacks - being held hostage, losing his index finger, the break-up of his marriage - the summits conquered and the fears overcome.
Fans of Free Solo and Dawn Wall, and climbers and non-climbers alike, will be gripped by this story of drive, focus and achieving the impossible.