I have nothing against narcissists — as long as they conduct their self-love affairs in the privacy of their own homes.

As far as I am concerned, though, to suffer this aggressively dull example of self-exposure by playwright Lisa Kron is like being held captive by an egotist who labours under the delusion that the conundrums of their private life will resonate with a wider public.

I am astonished that Kron’s Well received two Tony Award nominations and that the New York Times described it as one of the best plays of 2004. Even my colleague Fiona Mountford gave the piece a three-star rating when presented at its Trafalgar Studios London premiere last autumn. A Pirandellian or meta-theatrical notion drives Miss Kron’s Well forward and left me distracted.

This black comedy masquerades as a staged autobiography in which Natalie Casey’s self-mocking Lisa looks back to schooldays, itemises allergies from which she recovered and explains how she reacted to the governing ironies of her chronically unwell mother’s life.

We gather the older Kron — Sarah Miles’s Ann, who sits rear-stage in cardigan and pyjamas and interrupts her daughter in simpering outbursts of aggrieved winsomeness — struggled to make America ideologically well by promoting racial integration in her own rather racist piece of America, yet has suffered a life-time of debilitating allergies.

Why do some good, liberal people like Ann succumb to the mysterious allergies while others, like Lisa, recover from them?

Miss Kron’s Lisa has neither answers nor stimulating questions. Her monologue is eventually sabotaged by actors who play characters in dramatisations of Lisa’s life, and by Ann who steps into her own daughter’s play to no revelatory purpose and without giving us any insight into stoically borne bouts of unwellness.

There are flashes of comic repartee in the course of all this rapt navel-gazing and self-contemplation. Eve Leigh directs. I do wonder why.

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