The Train Driver, Hampstead Theatre, London

The Train Driver had its genesis in a newspaper report that hooked and haunted the great South African dramatist Athol Fugard after he read it in December 2000.

A woman had left her squatter camp and killed herself and her three children by stepping in front of a speeding commuter train. A particularly devastating detail was that no one came forward to claim the bodies.

For Fugard, the story bleakly symbolises the inequalities that persist in a rainbow nation still shadowed by the legacy of apartheid. But in trying to write about the deceased mother, he was brought up short against an inability to comprehend the degree of hopelessness that had pushed her to that desperate act. So he switched perspective and looked at the event through the eyes of the "seriously traumatised" train driver. The latter's painful emotional journey is the subject of the play, which now arrives from Cape Town in the author's own moving, beautifully modulated Fugard Theatre production.

A 90-minute two-hander, the piece is set in a makeshift graveyard on the outskirts of Port Elizabeth, where the woman and her child are buried among the other nameless paupers. Tormented by the moment when his eyes locked with hers just before his train mowed them down, the Afrikaaner driver, Roelf Visagie (an excellent Sean Taylor), has come unravelled, abandoning wife and family in a quest to confront the woman in her final resting place, even if only to curse her for destroying his life. His agitation is contrasted with the slow-paced stoicism of Simon, the elderly African grave-digger (a lovely, sensitive performance by Owen L Sejake).

The shifts in Mannie Manim's superbly graduated lighting design mark the days and nights that go by as Roelf's rage slowly turns into understanding. You could certainly argue that Simon's role is underwritten and that we learn far too little about him. But you'd have to be chronically cynical to dismiss the piece as a self-indulgent white guilt-trip. There's a tremendous depth of feeling, and anguished authorial identification, in Roelf's edgy transition from a confused, vindictively resentful guiltiness to a sober acceptance of his true, broader complicity, as a white man, in the misery he has witnessed during his search.

To 4 December (020 7722 9301)