In the autumn of 1502 three giants of the Renaissance period - Cesare Borgia, Leonardo da Vinci and Niccolò Machiavelli - set out on one of the most treacherous military campaigns of the period. Cesare Borgia was a ferocious military leader whose name was synonymous with brutality and whose reputation was marred with the suspicion of incest. Niccolò Machiavelli was a witty and subversive intellectual, more suited to the silken diplomacy of royal courts than the sodden encampments of a military campaign. And Leonardo da Vinci was a visionary master and the most talented military engineer in Italy. What led him to work for the monstrous Borgia? And what attracted him to the cunning Machiavelli? In his extraordinary new book acclaimed historian Paul Strathern ingeniously focuses on this improbable collusion of three iconic figures of the Italian Renaissance to unite three mighty strands of the period - war, politics and art. As each man's life unfolds, so does the Italian Renaissance.