The Stone, Royal Court, London

People who live in past houses shouldn’t sow stones: that seems to be the moral of Marius von Mayenburg’s ridiculously short one-hour play that kicks off a German season in Sloane Square and sends you scurrying to the programme text on the way home to make sure you know what happened.

Or, rather, what didn’t happen. The buried stone is one thrown at Wolfgang for allegedly helping Jews to escape the SS before the war. His widow and daughter, Withi and Heidrun, have returned to the East German house in 1993. We flash back to 1935 as they buy the house, to 1978 when they sell it on to three other families, and to 1945 as the bombs are falling.

While Heidrun, played with square-jawed ferocity by Helen Schlesinger, scrabbles about for the stone, sullen Stefanie (Amanda Drew) from the 1978 crowd accuses her of not sending her chocolate bars from the West on her birthday and asks whether they swung on the swing towards the house or towards the forest.

Still worrying about the significance of this, we are suddenly hit with the possibility that old Wolfgang (Jonathan Cullen) was a Nazi bad guy after all. Or did he, like Stefanie, swing both ways?

Then there’s the matter of the spikes on the walls. Linda Bassett’s not-very-with-it old Withi is clearly told by Mieze Schwarzman (Justine Mitchell, in a fetching floral dress), the attractive Jewish lady whose husband is Wolfgang’s boss at the veterinary institute and who sells them the house in 1935, that they put up the spikes, and not just for decoration.

Next thing, old Withi is telling boastful big ones about how she put up the spikes, as though claiming credit for the garden rockery and fairy lights that were there all the time. Turns out, too, that Stefanie wants her life back (don’t we all), as well as the chocolate, and that Mieze took an axe to the piano so the Nazis couldn’t play the wrong sort of music on it.

The writing in Maja Zade’s translation is elliptical in the wrong sort of way, piling puzzle on confusion without jabbing us awake with irony or |wit. The actors play valiantly in a bare sky-blue box (designed by Johannes Schutz), and Ramin Gray’s production boldly refuses to differentiate between eras except in the words themselves; we get the guilt, but not the gilt edge.

To 28 February (020-7565 5000)