Paul Cézanne and Emile Zola began a childhood friendship that would link their destinies for life: they shared not only a geographical origin, social and educational background, and intellectual interests, but also a deep complicity. Despite their different artistic fortunes--Zola achieved early recognition and success, while Cézanne, isolated, barely exhibited his work until the end of his life, thanks to Ambroise Vollard--they maintained a fruitful dialogue for thirty years, even after the publication of The Work in 1886, in which Zola supposedly portrayed his painter friend in an unfavorable light. These letters show in a new light the richness of a friendship as complex as it was genuine, and the singular sensitivity of two artists who had the privilege of knowing each other and celebrated it by opening up about their most intimate artistic and personal concerns, often indistinguishable for both.