Fen / Far Away, Studio Theatre Sheffield

Globalisation surfaces in vividly diverse forms in the two plays that make up the first programme in Sheffield Theatres' well-conceived and welcome season of work by Britain's boldest and most persistently original dramatist, Caryl Churchill.

Globalisation surfaces in vividly diverse forms in the two plays that make up the first programme in Sheffield Theatres' well-conceived and welcome season of work by Britain's boldest and most persistently original dramatist, Caryl Churchill.

Fen (1983) evokes a world in which ownership of the countryside is shifting from feudal landlords to multinational corporations. The bitter irony is that the stunted lives and backbreaking toil of the fenland women, whom we see picking potatoes along the furrows of damp earth on Gemma Fripp's bleakly evocative set, remain essentially unchanged. The hopelessness and anger get turned inwards. Self-mutilation and torture of the weak have become ways of confirming existence. If you can feel or inflict pain, you must be still there.

Playing 20-odd parts, Simon Cox's excellent cast of six conjures up a powerful sense of a community going nowhere but down. It's amazing how much detail and insight Churchill manages to pack into a succession of spare, short scenes that here succeed each other with a heightened, dream-like fluency. The effect is a haunting blend of intimacy (often dourly comic) and (with roles deliberately cast regardless of age and looks) objectifying defamiliarisation.

The globalisation in Far Away (2000) takes the form of a savagely comic vision of a planet embroiled in a war where even the animal species have turned ruthlessly partisan ("the cats have come in on the side of the French").

With lethal levity, and without once mentioning religion, Churchill's black zoological tease brilliantly satirises the whole pernicious notion of categorising and rating people along essentialist lines. The once-castigated deer become dewily sentimentalised personae gratae once they switch allegiance to "us" ("Their natural goodness has come through. You can see it in their soft brown eyes"). These are sentiments with which George "Axis of Evil" Bush would fervently concur.

Far Away jolts forward in three short acts. Kathryn Drysdale is a mesmerising mix of troubled, implacable curiosity and exploited trust in the first episode where she plays Joan, a little girl unable to sleep, who quizzes her lying aunt (the excellent Valerie Lilley) about what she has just accidentally witnessed: an act (we deduce) of bloody, surreptitious ethnic-cleansing. We then jump to Joan as a young woman employed in a hat-maker's that constructs fantastical millinery that the authorities force prisoners to wear in degrading fashion parades before they are executed. Shades of Abu Ghraib here.

Cox's staging choreographs the hat works episodes with a geometric precision and deadpan humour. It's less good than Peter Brook's production at suggesting any psychological through-line in the story of Joan who, played by yet another actress, is finally seen caught up in the global conflict. But you're left in no doubt that Far Away deals with matters close to home.

To 19 June (0114-249 6000)