If there is a message behind French writer Florian Zeller's utterly absorbing black comedy it might be that no relationship can survive the complete truth. The set-up is very familiar. Michel is having an affair. Less predictably, the affair is with his best friend's wife. It's all being conducted with characteristically Gallic savoir faire until it dawns on Michel that he may not be the only one doing the betraying.

It's impossible to go into plot detail here without turning this review into one long spoiler. In fact, critics were given the script with the request not to open it until after the show. And a good thing, too. But it is possible to say that, whether by design or accident, Zeller's play is like watching a comedy version of Pinter's Betrayal. And, like that play, the humour here reveals the self-denying hypocrisy of those who hate being treated in the way they treat others.

As Michel, Alexander Hanson turns that kind of selfishness into an art. He exhibits monumental incredulity at the idea that what is good for the gander is also good for the goose. He's terrifically supported by Tanya Franks as his wife, Frances O'Connor as his mistress and an unsettlingly calm Robert Portal as his best friend.

Christopher Hampton's translation, and Lindsay Posner's terrific production, might have injected a degree of English moralising into the situation. There is something Anglo-Saxon about Michel's unravelling panic. You can imagine a French production performed with deadpan gallic insouciance, which might be even funnier.

Still, it has stacks of French style and Posner skilfully prevents this English version of a French comedy of manners from becoming an Ayckbourn farce.

Fans of the previous Zeller plays to have reached these shores - all translated by Hampton - were wowed by this prolific writer's ability to subvert everything the viewers think they have learned about the people on stage.

And even though, structurally, this is a much more conventional play than those works - and Pinter's time-shifting Betrayal, for that matter - Zeller still exhibits a remarkable ability to make his audience constantly reassess what is going on.

When, finally, the whole truth is revealed, they are left to ponder the author's dark observations about humanity. None are more damning than our ability to claim the moral high ground while actually living in its deepest valley.