In 1975, accepting an honorary degree at Oxford, Henri Cartier-Bresson held a blank sheet of paper over his face to avoid being photographed. This episode explores how the most famous photographer of the 20th century came to crave invisibility, from a rigid bourgeois childhood in a wealthy sewing-thread family, through Cubist training under André Lhote and cafe afternoons with the Surrealists, to a heartbreak that sent him to the Ivory Coast, where he hunted game at night and nearly died of blackwater fever.

We trace the Martin Munkácsi photograph that made him abandon painting for a 35mm Leica, his nearly three years as a prisoner of war and three escape attempts, the founding of Magnum Photos in 1947 with Robert Capa and David Seymour, and the 1952 book that gave the world the phrase the decisive moment. We also look at his strict rules,  ...