In this diary of a genius, Leonardo's voice invites us to go through his most intimate world: his obsessions, his inventions, the artistic commissions of the monarchs, the rivalry with Michelangelo, the genesis of The Last Supper, the encounters with the Mona Lisa, from which that pictorial icon of beauty and sensuality would be born: “I had agreed to paint the portrait of a lady whose face was from another world […]. To please her and make her feel comfortable, I hired a group of minstrels so that, on her face — but above all in her heart — there would always be her smile ».

With unparalleled skill in handling ink, Ralph Steadman recreates the artistic atmosphere and the political situation of his time, while, with strokes full of fine humor, he brings to life the most influential characters in who has been considered the Renaissance sage model. Stedman developed a strong obsession with Leonardo, a fixation that led him to paint his own version of The Last Supper on his bedroom wall; to build a machine equivalent to Leonardo's, which managed to take flight; and to go through those Italian cities and landscapes traveled by Da Vinci, trying, thus, to imagine what it was like to inhabit the imaginative mind of a spirit without limits. Immersed in the creation of the book, Steadman said, "I became a Leonardo. Without having to read Kenneth Clark."