In a lifetime of theatregoing you will not often - indeed you may never - encounter an eccyclema. In the last two months Yorkshire has seen three. In the Northern Broadsides Antigone we had two, masquerading as superannuated hospital trolleys, and now, in Euripides's Medea at the West Yorkshire Playhouse, we get the third, as the wall of Medea's apartment is collapsed to reveal the dead bodies of her two small sons upon their bier.

The eccyclema is a stage device in classical Greek tragedy for revealing the corpses to an audience which has been denied the actual spectacle of the dirty deed - it being axiomatic that Greek theatre displays not action but the before and after thereof. Mention of it here is not trivial, since Alistair Elliot translation of the play, originally made for Diana Rigg's performance at the Almeida in 1992, is here seen in a production which was fanfared in advance as marrying Greek theatre with the traditions of the Yoruba tribe of Western Nigeria.

Evidence suggests, however, that somewhere in the production process a divorce occurred, since the announced consultant on Yoruba tradition has been dropped from the credits, and the live music and song which he was to perform within the show are not there. Furthermore, the promised stylised and ritualised techniques, taken from Yoruba tradition, which were going to bring us the spectacle of "the full horror of Medea's murders", aren't there either.

What we are left with - to this reviewer's eyes, which are admittedly not finely attuned to identify what scraps remain of African theatre - is a pretty good, straight reading of the Euripedes original. True, it’s played by an entirely black cast on what appears to be a cracked biscuit of earth, which the chorus of Corinthian woman ritually sanctify before the play commences.

But the magnificently statuesque Tanya Moodie - whose largely quiet, tortured stillness as Medea makes her eventual outpouring of passionate revenge utterly devastating - gives a fine classical performance that requires no arcane exegesis. Her revelation of her sons' bodies is as chilling a moment of theatre as you could hope to experience.

Femi Elufowoju Jr (who also directs) contributes a bare-topped Jason who certainly looks more African than Greek but whose specious self-justification owes everything to Greek philosophical discourse. He is manifestly Medea's inferior both emotionally and intellectually, and Elufowoju's performance is generously restrained in acknowledgement of the fact.

Not quite the cross-fertilisation of theatrical traditions that we expected, then, but a workmanlike production with a performance of rare beauty at its core.

- Ian Watson