BWW Reviews: PROOF, Greenwich Playhouse, May 12 2011

Robert (Marcus Taylor) is desperate to prove that he can still work, still spark the mathematical genius that flamed in his early twenties. His elder daughter, Claire (Amy Burke), must prove that she has her family's best interests at heart whilst suspecting, guiltily, that she is really doing what is best for her. His student, Hal (Dan Cohen) must prove that he trusts Catherine and that he loves her at least as much as he loves her father, his doctoral supervisor. Younger daughter, Catherine (Holly Easterbrook), must prove that her spectacular proof of a mathematical conjecture is indeed her work and that she has inherited her father's mathness not his madness.

It's a heady mix, all that brilliance and bonkerness crammed into the intimate space of the Greenwich Playhouse and David Hutchinson's direction never drops the pace for a moment. All four performances are beautifully judged - Dan Cohen's nervous geekishness reminding me of Woody Allen's 70s work and Amy Burke showing us exactly why Claire has turned out so hideously selfish, pulling off that most tricky of acting briefs: the eliciting sympathy for an unsympathetic character. Marcus Taylor makes us wonder whether he is really as mad as everyone says, until his final appearance in which he leaves us in no doubt. Holly Easterbrook, perhaps a little too well turned out to convince as a woman who cares nothing for normal social interaction, effortlessly shows us why Hal, who worships her father with the intensity that only the very good generate when confronted with the great, would pursue her for years. That Catherine never appears anywhere near a spiralling descent to madness, just makes her sister even more repulsively self-serving, cranking up the intra-family dysfunctionality another notch.

If this all sounds a little, well, intellectual and ever so slightly worthy-but-dull, it's not - there's plenty of humour in the unapologetically sparkling conversation that seems the preserve of the American intelligentsia, a class unconcerned by class. It's a million miles removed from the easy manipulation and stereotyping of "A Beautiful Mind", a movie also featuring a troubled mathematical genius. Given Pulitzer Prize winning material with which to work, but little in the way of the bells and whistles of a lavishly funded production, Sell A Door Theatre do it full justice, proving, as if we didn't know it, that the play's the thing.

Proof continues at the Greenwich Playhouse until 29 May.