Afterplay by Brian Friel, directed by Malcolm Robinson with Lewis Fiander and Lyndel Rowe, until July 11 at Fortyfivedownstairs, Flinders Lane.

Sometimes I think my passion for theatre - and I suppose I have to call it a passion - is purely a pleasure in watching actors. This isn't entirely true, theatre being the nexus of so many arts, but it's true enough. Perhaps it's partly that I've never had any ambition to act - I will never understand it from the inside. To watch a consummate actor at work evokes in me a kind of wonder, like Franz Kafka watching typists in awe at their ability to use the machine: there's something arcane and mysterious about it, a bewitchingly fragile courage, a generosity which is the exact reverse of narcissicism.

And actors don't come much more consummate than Lewis Fiander. When he's on stage, you can't stop watching him. He never drifts off into abstraction or vagueness, even if all he has to do is sit still and listen. The entire length of his lanky body is all living attention, and his nobly aged face seems to have been designed especially to express nuance and complexity. He might have been born to play Chekhov, that master of human finitude, whose characters orbit their frustrated passions through the suffocating trivialities of their lives, flickering through hope and despair and resignation like poignantly brilliant stars.

In Afterplay, Brian Friel's tribute to Chekhov, Fiander is almost doing that. Friel has taken up what has recently become a common conceit, to take the characters from a classic work and imagine them further than their authors did; so we have versions of Dickens by Peter Carey, or new takes on Jane Austen. I have sometimes wondered what prompts writers towards such exercises, since it wavers dangerously close to a kind of fetishisation; surely a more interesting tribute would be in a truly imaginative expansion of what another writer does, in taking an influence and running with it (as you might argue that Beckett did with Chekhov - these two playwrights seem to me to be profoundly related). But still, when it's done well it can have its virtues, and with a playwright like Friel you can be sure it will be well done.

Friel takes two characters from two of Chekhov's plays, Andrei, the brother in The Three Sisters, and Sonia from Uncle Vanya. Friel has enough skill as a writer to pull off a creditable ventriloquisation of the master. In Afterplay, Sonia (Lyndel Rowe) and Andrei (Lewis Fiander) meet in a shabby Moscow cafe some two decades after the events of the plays. They have fallen on hard times; Sonia is facing the progressive loss of her estate, and Andrei is now forced to busk in the streets, his "useless" culture earning him a living at last. Sonia's practical veneer gradually crumbles to reveal that she still cherishes a burning, hopeless love for Dr Astrov, a passion she will not abandon. Andrei sustains himself by a series of "little fictions": that his wife did not leave him, but died instead; that his children are successful and close to him; that he is a violinist in the orchestra for La Boheme, rather than busking in the Moscow streets with a mediocre balalaika player from Uzbekistan.

The faded remains of the middle class in revolutionary Russia, they can think of the future only with fear. And the biggest fear, for both of them, is loneliness. Like Chekhov, Friel gradually exposes how people create an insulation of dreams to defend themselves against the emptinesses in their lives, stripping away their illusions to reveal the touchingly irrational passions which animate their lives. The effect of all Chekhov's plays is to create an almost unbearable feeling of human mortality, a sense of inevitable darkness encroaching on tiny, exquisitely fragile pools of light. This endows the minutae of life with a piquant significance: the smallest gesture, no matter how futile, is transformed into an act of defiance. Friel goes a long way to achieving this sense, but he is not Chekhov; Afterplay has a more limited idea of passion, and while Friel can emulate Chekhov's skill in exposing human triviality and his sense of comic tragedy, he can't match the ultimate grandeur and pathos of Chekhov's vision.

However, it's enough for the actors to go on, and the performances make this production well worth the price of admission. As the pragmatic, stoic Sonia, Rowe is an excellent foil to Fiander's Andrei. Both these vastly experienced actors give detailed performances of great feeling, and capture with beautiful precision the shifting layers and comic contradictions of their characters. Fiander is unarguably brilliant, and Rowe never less than excellent. I think Rowe's performance suffered a little for me because an extraordinary portrayal by Melita Jurisic many years ago has indelibly coloured my image of Sonia; for all her skill and feeling, Rowe's more restrained performance couldn't dislodge Jurisic's throbbingly lyrical passion from my mind.

Malcolm Robertson's production is about as simple as a production can get: the design is a sketch of greys, browns and blacks against the white wall of the space, which immediately gives it a sense of shabby nostalgia, like an old sepia photograph. The set consists merely of three cafe tables and a cupboard, and the lighting states and sound are minimal. All the focus of the production is on the actors, and it's fair to say that the acting repays the attention.

The only real problem I had was with fortyfivedownstairs itself: the play is presented front-on with the audience seated in rows the length of the theatre, and this doesn't solve the inherent problems this space has with sightlines and acoustics (though I hasten to say the play is always audible). Ideally, this play should be presented in an insulated proscenium like the Playhouse; the performances, all subtlety, nuance and subterranean passion, would blossom under the amplification and focus. And frankly, they deserve such framing. Alas, this is not an ideal world, and to see some of the most accomplished acting on in Melbourne at the moment you will have to bear, with Chekhovian stoicism, the limitations of the theatre itself.

Fortyfivedownstairs