An excellent biography and cultural history that sets Foucault's philosophy into the context of his life, and his life into the context of his times. The result is a particularly illuminating description of the second half of the twentieth century. Miller considers Foucault in relation to his influences (Sade, Artaud, Bataille, and especially Nietzsche), his love/hate relationship with Sartre, his relationship with his philosophical peers (Derrida, Barthes, Chomsky, Habermas, Deleuze, etc.), and his history of political engagement, especially during May '68 and the Iranian Revolution.
But the main focus of the book is the integration of biography and philosophy, with particular emphasis on Foucault's sexuality - his interest in S&M and his homosexuality - in relations to his interest in marginalized groups and violence. Foucault's death from AIDS and his frequent presence in the gay bathhouses of San Francisco is one of the key points of the text, particularly the possibility that he engaged in unprotected sex while aware that he was dying, and probably aware that he was dying from AIDS. His experimentation with drugs - marijuana, LSD and opium - also receives a fair bit of attention.
The book gives the impression that Foucault was prone to histrionics in his writing, always a bit overwrought and dire.