Anton Chekhov's characters, like so many of their compatriots these days, it seems, are relocating to these shores. This autumn, his Three Sisters will be shifting to the Brontë Parsonage museum in Haworth for Blake Morrison's latest Northern Broadsides adaptation, while his Uncle Vanya has already been comfortably resettled in Ennerdale, thanks to Alan Ayckbourn. Ayckbourn's transposition of the story and characters from an isolated, 1890s Russian estate to the Lake District in 1935 is complete and convincing. This is only partly due to cannily altered cultural references: vodka becomes whisky; environmental concerns shift from deforestation to recent Forestry Commission afforestation; name changes give class clues – Ivan Petrovich Voinitsky (Vanya) becomes Marcus. It's the very success of the transposition, though, that nearly smothers the play – the first two acts feel so much like a stolid, between-the-wars country- house drama. Chekhov's multifaceted characters seem over-simplified; the pace of the action slows, at times, from leisurely to leaden. Then, after the interval – wham! Chekhov-Ayckbourn fission – a fireworks display of farce, comedy and tragedy around a dining table. The confrontation between Terence Booth's pompous professor and Matthew Cottle's wounded Vanya/Marcus (two belting performances) shreds reticence, bares hearts, exposes nerves. Facades now shattered, the first half makes sense. The shared genius of Ayckbourn and Chekhov – penetratingly realised by the entire cast and crew – is to reveal the unique individuals beneath their (British or Russian) social layers.