Joanna Murray-Smith's domestic four-hander was first seen in her native Australia and now receives its UK premiere at the National, its setting relocated to the literati haven of north London populated by an all-British cast to die for.

George (Corin Redgrave) and Honor (now Dame Eileen Atkins) have been married for 32 years, their insecure daughter Sophie (Anna Maxwell Martin), now in her 20s, finding succour in the charm of her parents' happiness. A prominent journalist, George is to feature in a book on the Movers and Shakers but when Claudia (Catherine McCormack) arrives to pen his profile, he's unsettled to have his own interview techniques - and a few other tricks - turned on him.

While Murray-Smith's play opens with some interesting intellectual sparring, once the inevitable seduction transpires, the story veers headlong towards the banal. In the grips of (slightly past) mid-life crisis, successful older man leaves family for sexy younger woman who makes him feel young/vibrant/brilliant/successful (insert other adjectives as appropriate). Meanwhile, abandoned wife realises how much she's given up to support husband's career then rediscovers her own talents and independence.

I kept thinking, at some point, there must be a twist on the obvious, more revelations about the secrets around which "one's life revolves" alluded to early on. But such plot punches aren't forthcoming - nothing much happens which, you sense, is just the way Murray-Smith likes it. There are no distractions from William Dudley's spare design either, an empty stage papered like the lined yellow pages of a journalist's notebook onto which the characters carry the occasional chair and other bits and bobs of domesticity.

The play's triangle of lovers are all writers - George the journo, Claudia the aspiring novelist, Honor the once award-winning poet - but while they have some great lines, none seem quite able to say what they mean; within a maelstrom of conflicting emotions, they don't seem to know themselves just how they feel at any moment.

Honor is by far the most sympathetic, not just because she's the wronged wife and shares her name (minus the 'u' - why?) with the play's title, but because Atkins invests her with much greater depth. From calm intellectual to disbelieving wife who asks her husband three times to repeat the line "I'm leaving you" and back again, Atkins gives a virtuoso performance. In the smallest role, Maxwell Martin is also sensational - the least articulate of the bunch and the most heart-wrenching. Redgrave also plumbs his crisis of ego well, while McCormack, as always, is believable as the predator bitter with the world for seeing her beauty before her brains.

What's the overlap between love, loyalty and passion? How do different generations view sacrifice? Is truth or kindness tantamount? Murray-Smith's questions don't differ much from what's on offer in the likes of Stoppard's The Real Thing, Nichols' Passion Play or other infidelity dramas, but the quality of her dialogue and the delivery it receives here from a superb cast in Roger Michell's spare production make it worth hearing them asked again.

- Terri Paddock