Frolicking around like a deranged sprite, throatily emoting like Joan Greenwood in overdrive, McEwan swans and swoons across the furniture, projecting fatal allure and compassionate regretfulness at its effects - both equally spurious. She has all the genuine feyness of an electronic calculator. After a riotous display of squiffy befuddlement - in which she manages to fall off a sofa while still keeping her drink upright - she's instantly back on the ball when Malcolm Sinclair's deliciously distraught diplomat sneaks a kiss and gives her the opportunity for one of those "big moments" with which she and her family ritually humiliate their guests.
Judith has no concept of "offstage" and to highlight the continuity between her trashy past roles and her bad behaviour now, Declan Donnellan's hilariously over-the-top production gives us a flashback to her glory days - a dreadful performance of the hoary melodrama she intends to revive.
Replete with Gothic setting, thunderclaps, and deathless exchanges, this interpolated prelude establishes the mad theatrical grammar on which life at the Blisses is patterned. It also gives a foretaste of their offhand manner of parenting. When her daughter declares that Judith's fond memories of her children in their perambulators have no factual basis, you remember the unceremonious way Judith's character in the melodrama dumped the dummy of beloved "little Pam" so she could continue her maternal histrionics unhampered.
Where bad manners and displays of "artistic" temperament are concerned, Donnellan vigorously ups the pollen count, creating a madhouse in which bananas are proffered instead of cucumber sandwiches, reducing civilised ritual to a chimps' tea party. One would rather weekend with the Macbeths than with the Bliss children, whose un-housetrained weirdness is joltingly conveyed by Monica Dolan and Stephen Mangan. All in all, a Hay Fever not to be sneezed at.
To 14 Aug (0171-836 8888). A version of this review appeared in later editions of yesterday's paper