Letters to Franca collects together the 500 extraordinary letters Louis Althusser wrote to Franca Madonia between 1961 and 1973. A collection of writings which reveal a different Althusser who Franca claimed, when commenting on the letters, "neither quite the same, nor quite another." as his public persona. The letters also narrate the most productive part of Althusser's intellectual life and the time in which his most characteristic works were elaborated and published.

The correspondence thus allows a unique insight into the 'laboratory' of Althusser's theoretical, institutional and political trajectory, offering an intimate account of the establishment of Althusserian Marxism and the intellectual, historical and political milieu within which it came to prominence. But the correspondence also, of course, charts the story of Althusser's relationship with Franca Madonia, encountered in 1961 and becoming Althusser's lover, intellectual confidante and Italian translator; the letters have an epistolary-novelistic quality and afford an intimate vision of an extraordinary relationship, the chronicle of a passion. In particular, the writing styles exhibited in the correspondence are exceptionally diverse: alternately analytic, passionate, lyrical, experimental, playful and sombre, displaying an investment in language and expression barely suggested by Althusser's previously published work.

At once a diary of an intellectual-institutional-politcal life and the narrative of a relationship, then, the Letters to Franca are also, uniquely, the first hand record of Althusser's manic depression, inviting the reader to follow its vicissitudes and effects upon his personal and public personae. The correspondence thus also has exceptional value as a record of Althusser's daily negotiation with his 'condition' and includes extensive reflections and observations concerning his own psychoanalytic experiences.