Physical theatre companies are often described as madcap or insanely funny, but none are quite as barmy as Ridiculusmus, a duo comprising David Woods and Jon Hough. Their investigation into madness, Yes, Yes, Yes, is one of the funniest and saddest things I have ever seen. So who could be better qualified to offer insights into the Troubles and the delusions of the Northern Irish peace process than this company, which for many years was based in Derry?
In Say Nothing, Kevin is a former local boy who, after taking a course in peace studies in England, has moved to Derry as a conflict resolution worker. This means that he runs conferences with titles such as Hands Across the Barricades, and encourages people from different communities to swap songs. But all is not going well for Kevin: his pregnant girlfriend has decided she is a lesbian, and his contact with the local community finds him up against a brick wall of prejudice at every turn.
All this sounds like rather trite and predictable satire. But what sets Say Nothing apart is its form, and the hidden depths that emerge as Kevin's growing frustration leads to a mental breakdown. The piece - set entirely atop a small suitcase of turf representing the Emerald Isle, in front of a corrugated fence upon which has been scrawled, "Decommission this" - takes the form of endlessly circular, repetitious conversations. They lay bare the myth of Irish hospitality and show that the elevation of the craic to an art form is actually a way of avoiding saying anything meaningful at all.
As an explosion of myths - "traditional Irish music", "traditional Irish welcome", "traditional Irish pipe bombs", "traditional Irish blow-your-kneecaps-off" - this is amusing enough. As a comment on the way language is used to obscure real intent, or, in the case of the Irish peace process, lack of real intent, it is clever and bleakly hilarious. A small but brilliant show.
· Until January 4. Box office: 020-7638 8891.