Stefano Dall'Aglio sheds new light on the notorious Florentine Lorenzino de' Medici (also known as Lorenzaccio) and on two of the most infamous assassinations of Italian Renaissance history. In 1537 Lorenzino changed the course of history by murdering Alessandro de' Medici, first duke of Florence, and paving the way for the accession of the new duke, Cosimo I. In 1548 Lorenzino was killed in Venice in revenge for the assassination he had committed. Basing his work on extensive research in the historical archives of Florence and Simancas, Dall'Aglio reconstructs the events surrounding these murders and involving the Medici, their loyalists, the Florentine republican exiles, and some of the most powerful sovereigns of the time. The first publication in a century, and the first work in English, to examine the life of Lorenzino de' Medici, this fascinating revisionist history is as gripping as a detective novel, as Dall'Aglio unravels a 500-year-old mystery, revealing that behind the bloody death of the duke's assassin there was the Emperor Charles V.