Four men in a cell in Rebibbia prison, Rome, awaiting trial on serious charges of subversion. One of them, the political thinker Antonio Negri, spends his days writing. Among his writings are twenty letters addressed to a young friend in France letters in which Negri reflects on his own personal development as a philosopher, theorist and political activist and analyses the events, activities and movements in which he has been involved. The letters recount an existential journey that links a rigorous philosophical education with a powerful political passion, set against the historical backdrop of postwar Italy. Crucially, Negri recalls the pivotal moment in 1978 when the former prime minister of Italy, Aldo Moro, was kidnapped and killed by the Red Brigades, and how the institutions then pinned that killing onto him and his associates. Published here for the first time, these letters offer a unique and invaluable insight into the factors that shaped the thinking of one of the most influential political theorists of our time and they document Negri's role in the development of political movements like Autonomia. They are a vivid testimony to one man's journey through the political upheavals and intellectual traditions of the late 20th century, in the course of which he produced a body of work that has had, and continues to have, a profound impact on radical thought and politics around the world.