Michelangelo and Leonardo lived five centuries ago, yet their works still suffuse our culture. They have been equally revered since their lifetimes, though we admire them mostly in isolation of each other. But in 1504 they competed with each other directly in a bid to paint the walls of a room in Florence's Palazzo Vecchio. This competition-perhaps the most significant in the development of Renaissance art, argues Guardian art critic Jonathan Jones, as it marked the moment at which individual style came to command its own value-has been largely forgotten because the rival works did not survive. Jones's unexpectedly riveting account re-creates this arena of 16th-century Florence with astonishing detail.