Otherwise Engaged, Criterion Theatre, London

Simon Hench, a publisher pushing 40, has set aside a day to spend alone at home listening to his new recording of Parsifal. We see him open this precious purchase, place the first vinyl disc on the turntable, and commune with the opening bars - whereupon his cocoon of peace is violated by his lodger (Liam Garrigan), a yobbish Liverpudlian sociology student, who denounces Wagner as a proto-fascist before characteristically cadging a fiver.

This is the cue for a non-stop succession of interruptions from distressed folk who need the concern and reassurance that Simon can only politely dissemble, because he is always otherwise engaged. These include his brother Stephen (Peter Wight), a teacher at a minor public school with an inferiority complex as big as his burgeoning family, and his friend Jeff, an ageing hired gun of Grub Street, whose drunken disenchantment with literature and foreigners is hilariously conveyed in the excellent performance of Anthony Head.

Swiftly following, there are Jeff's much younger, poisonously ambitious girlfriend, Davina (Amanda Ryan), who is willing to bare her breasts and more for the chance of being published; a sexually arrested schoolfellow (David Bamber) whose fiancée, chosen because of her resemblance to his boyhood idol, has just been rogered by Simon; and his unfaithful wife, Beth (Amanda Drew).

In the encounters between Simon and his visitors, the mess of living is hurled against an order and control that have been bought at a price that the protagonist is too sealed-off to appreciate, until it is too late. He's the kind of man whose imperturbable poise drives others frantic.

A stickler for verbal precision, he deflects the charge of being "indifferent" by questioning the terms - indifferent in the sense of an indifferent wine? Aware for 10 months that his wife has been unfaithful, he has preferred to let this pass insultingly unnoticed - even savouring the guilty, increased intensity of her love-making - because he wants a selfish, semi-detached life.

Unfortunately, Richard E Grant doesn't have the stage presence or the sense of irony needed for this role. He is too bland and Teflon-like in his invulnerability.

Alan Bates, who created the part and went on to play it again in the 1996 sequel Simply Disconnected, was brilliant at suggesting a closely guarded inner complexity and was very funny in the way he twitched his features into a semblance of concern and pitched his lines somewhere between the solicitous and the sardonic.

By comparison, Grant seems terribly straightforward and lacking in layers of sophistication. The rest of the cast, though, are spot on. Amanda Drew superbly projects the smouldering, indignant hurt of the underestimated wife and David Bamber skilfully radiates the moral BO of the aggrieved masochist.

Showing how life catches up, even with the doyens of self-management, this is - despite the central miscasting - a pleasurable and rewarding evening.