A Touch of the Sun, by David Evans

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Morning in Victoria prison under the apartheid regime smells of the warder's half-chewed egg sandwich and the recently emptied sanitary pots. Simon Brown, a South African political prisoner released after seven years inside to a further five of house arrest, hugs his sister Kathy, who smells of "soap and scent and skin... coffee and tobacco". This world outside, sensual and sweet, is shatteringly different to the one Brown knew previously, not least because it is now impregnated with memories of the past: "the people I've been hoping to see. The people I'm afraid of seeing," and "the people I'll never now see: the banned, the exiled, the imprisoned, the dead."

From this bleak moment of liberation, David Evans's novel leaps backwards, this time with a portrait of Brown as a racist adolescent in South Africa, believing in white supremacy. It details the gradual cracking of that identity, and builds toward the climactic moments of Brown's involvement in direct action.

Avoiding all clichés of heroism, all easy romanticisation of the struggle against injustice and oppression, Evans shows us a politics rooted in the mess and muddle of life, political activists who are not saints but flawed, passionate, suffering human beings. Simon Brown grows up white in a scruffy, impoverished family. Songololo Street, precisely in the middle of the social scale, demonstrates the tensions of segregated neighbourhoods. The "broad potholed road with its chipped kerbs and clogged gutters" is lined with single-storey houses: "Every second house had a concrete bird bath and ferns crowded most verandahs: Songololo Street residents cared about the look of things, unlike the inhabitants in Pretorius Street, two blocks away... too lazy, drunken, or defeated to bother".

The geography of apartheid means that the local black population lives in the distant township, reduced, when the rains flood it, to impassable mud, and the rich white folks in their own spacious district. Brown avoids going to Ramisamy's shop, because it is full of the "kaffers" he reluctantly learns to refer to as Indians and Africans. As long as he is able to look down on the local black and Coloured communities, Brown can maintain a fragile sense of self.

Puberty, however, brings vulnerability: as soon as he begins desiring girls he becomes unwillingly conscious of other people's power. The boys at his white school may pull on their masculinity as character armour, but they are in thrall to the posh white girls who dole out sexual favours according to the patriarchal rules about preserving virginity.

Simon fancies wealthy, liberal-minded Elizabeth, but she thinks he is dirty and taunts him for being dark-skinned. Sex radicalises Simon. His lust is the chink in his defences. He begins to notice how friendly his mother is with Joshua, a "Coloured bastard... who didn't know his place"; how much his sister Kathy enjoys the company of her Indian girlfriend Shantih, with whom he discovers she is having a secret affair; how the hypocritical old white men abuse black prostitutes. When he starts to work on the local paper, reporting court cases, he witnesses an immorality trial brought on the basis of an affair between a European man and his Coloured partner.

The dignity of the victims haunts him. He begins to become drawn in, unwillingly, to the Africans' struggle. Eventually, after witnessing police brutality in the aftermath of the Sharpeville massacre of 1960, he becomes a reluctant dissident, making alliances with African and Coloured activists, conducting a passionate affair with a young African woman and finally getting involved in sabotage and murder.

Evans's gripping story, dramatic as a thriller in its dénouement, confronts the reader with questions about our own capacity for honesty, for moral and physical courage, for commitment. His Simon Brown is a real and sympathetic hero.

Michèle Roberts's latest novel is 'Reader, I Married Him' (Little, Brown)