With this sorrowful drama, August Wilson completed his astonishing ten-play sequence covering the black American experience decade by decade through the 20th century. In Gem of the Ocean, set in the century's opening years, the characters included elderly ex-slaves, and the setting was a former “safe house” in Pittsburgh, the city where Wilson was born and where he set all but one of these plays. When Radio Golf brings the century to its close, Harmond Wilks, grandson of one of those characters, is running for mayor.

Thus far have conditions changed for black Americans, but one of Wilson's major concerns is to identify what has been forfeited during this ascent. Roosevelt Hicks (Roger Griffiths), a schoolmate of Wilks and his partner in a plan to redevelop Pittsburgh's Hill District, is shown to be hungry for assimilation. Eager to be the token black in a white-owned radio station, and severing himself from Wilks when his campaign goes belly-up, he is the object of the author's scorn and given no redeeming quality.

Wilson's view that assimilationists are denying their ancestry is vigorously put by the play's most engaging character, Ray Shell's honourable ex-con, significantly called Sterling. But the implications are ignored, and the argument itself is hard to follow.

For those who haven't seen other plays, the significance of the unseen character Aunt Ester will have to be taken for granted, a serious fault in a play that might not have taken its final form when Wilson died three years ago. Presented as a sort of folk priestess in the very first play, when she was already a couple of hundred years old, she represents a heritage threatened when a people ignores its past. The disputed ownership of her Hill District house, threatened with demolition, is the engine of the play.

The symbolism is potent but I found it muddled by the folksy jokiness of its long-time resident, Old Joe (Joseph Marcell), who is probably another symbol. And the character of Wilks is all too simply drawn - honourable, yes, and troubled, qualities clearly shown by Danny Sapani (pictured above with Julie Saunders), but he is required to mull over his changes of heart in silence.

This leaves holes in the play which, on its own, feels incomplete. But it only faintly diminishes Wilson's remarkable achievement in creating this sequence, making him the most significant American playwright of the past quarter century.

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