First Night: Afterplay, Gielgud Theatre, London

A drab, puzzling answer to a low-brow question

"Hello – you don't know me, but we're by the same author.'' We don't hear this chat-up line in Brian Friel's play, but we could. Twenty years after the time of the Chekhov dramas in which they first appear, Andrei from The Three Sisters runs into Sonya from Uncle Vanya.

"What happened next'' is a theme usually pursued by low-brow authors in sequels to Pride And Prejudice or Gone With The Wind. Friel is well above that class, but the idea is still impertinent, and this 70-minute play is a drab and puzzling work. Starting with the title, which misleadingly suggests post-coital caresses, everything about it seems off.

Sonya is going through a pile of financial documents when Andrei enters, in evening dress, carrying a violin case. The day before, the two had met for the first time at a Moscow café, its rusty chairs and tables a sad contrast to pre-Revolutionary fluted columns and etched glass.

Both are at a low ebb – he exhausted and far from an unhappy home, she trying to be brave in the face of the bank's taking over her affairs. But these mishaps are hardly surprising. As those who have seen the earlier plays will know, Andrei, the clever sisters' dull brother, married a vulgar woman who came to despise him; Sonya, a wallflower pining for the one attractive man in the district, was facing a lonely, bitter future. These two sad cases, who have never really lived, are burnt out by now.

Their news from home is depressing too – Uncle Vanya has died of a stroke, after a visit from the beautiful Yelena reawakens his unrequited love. One of Andrei's sisters has killed herself, and his wife is long dead. "How long?'' asks Sonya. "I really don't know.''

The only drama in their exchanges is Andrei's confession that he lied about a few things he said yesterday, and Sonya's growing realisation that he lied about much more than he cares to admit. But the truth – and Andrei's efforts to conceal it – merely show him to be even more pathetic. Sonya also tells a lie, but one would have to be familiar with Uncle Vanya to know this.

The banal remarks of these sheepish characters fail to engage us, and the anglicising of the text and the playing makes them even more unreal. Sonya refers to Mikhail Astrov as "Mikhail'' and calls lying "bloody'' – both unlikely from a prim spinster to a stranger in the 1920s. Neither actor attempts a Russian accent – indeed, Penelope Wilton, in a coat and skirt that could be worn today, is the epitome of a brisk, middle-aged head girl.

John Hurt does a great deal more with Andrei. His expression when Sonya inadvertently finds him out tells us more than half an hour of dialogue. However, it's hard to believe this intelligent and personable actor is a hopeless fool.

Strangest of all, the characters say nothing about how they have been affected by the revolution of 1917, surely their point of greatest interest. Sonya even says that Dr Astrov is still "caught up in schemes for saving the world", as if the Bolsheviks hadn't put some of their own ideas into practice.

No, if you want to see what Friel can do with Chekhov, try to get into the Donmar. His sparky translation of Uncle Vanya there shows him as the great man's happy collaborator, not his woeful competitor.