There's something peculiarly English about Ridiculusmus. From the whimsy of their first show Three Men in a Boat, to their journey found the Raj in Yes Yes Yes, this is a company with an old-fashioned and rather charming vision of English eccentricity. Clearly, therefore, they must feel like fish out of water in their adopted home-town of Belfast. And it is the direct experience of being English in what is (essentially) a foreign land, that has fed into the company's latest show, Say Nothing.

The frantic physicality for which the company is known is radically curtailed here. Employing a stunning visual conceit reminiscent of Beckett's Happy Days, David Woods and Jon Hough perform the entire show from within the confines of a suitcase. An effective metaphor for the tiny province that has long been the centre of such terrible strife, the suitcase is lined with turf – the green, green grass of Ireland (the emerald isle). Though physically constrained, the duo's other characteristic feature – their love of complex and often nonsensical language and their delightfully dark sense of humour – are in abundant display here. Woods plays Kevin, an Englishman with a PhD in Peace and Conflict Studies who's come to Ulster on an EU-funded programme, 'Hands Across the Barricades'. The world he encounters which is fleshed out by a marvellous array of idiosyncratic Irish personalities played by the perpetually dour Jon Hough is introverted and impenetrable. In this climate, nothing Kevin can do is right, despite his optimism and good intentions.

Say Nothing is a complex collage of personal observations on the Anglo-Irish conflict and, one suspects, a journey of personal catharsis for its creators. It's also compelling, intelligent and challenging and confirms the company's place at the top of the pile of British experimental theatre-makers.