Charly Gaul is a forgotten cycling legend. Once a household name across Europe, the diminutive Luxembourger won the 1958 Tour de France and the Giro d'Italia twice. A unique rider, Gaul was supremely gifted at climbing and resilient even in the foulest weather. His pedalling style was smooth and swift, and he could set an unmatchable metronome rhythm on a mountain climb. 'Mozart on two wheels,' was how one contemporary writer described him; another dubbed him 'The Angel of the Mountains'.

At the end of his cycling career Gaul disappeared, becoming a hermit living in a forest in Luxembourg. What drove Charly Gaul into a recluse's life? In Angel of the Mountains, Paul Maunder seeks to uncover the truth about Gaul, his psychology and the circumstances of his withdrawal from society. In rediscovering Gaul's enigmatic life, we find not only an unlikely hero but also a larger truth about the nature of sporting success.