This biography of Govan Mbeki (1910-2001), activist and intellectual, goes beyond the narrative details of his long life. Drawing on lengthy interviews with 'Oom Gov', it analyses his thinking, expressed in his writings over 50 years. This helps establish what is distinctive about him: as African nationalist and as committed Marxist - more than any other leader of the liberation movement, he sought to link theory and practice, ideas and action. The biography also explores controversial aspects of Mbeki's personality and career: his reputation as a hardliner, the personal and psychological price paid for militancy, and his role in the tensions within the ANC leadership on Robben Island.