First Night: The Year Of Magical Thinking, Lyttelton, National Theatre, London

Emotive Redgrave lacking in magical quality of diffidence

A double loss at the heart of the family would hit anyone hard, but David Hare is right to suggest that Joan Didion, the celebrated American writer, was quintessentially the wrong kind of person to suffer two sudden bereavements.

To a woman of her over-controlling inclinations, death offered the most devastating of challenges: to admit that there are crucial matters that may defeat even the sharpest organising ability and most assiduous research.

Her husband of 40 years and frequent collaborator, John Gregory Dunne, dropped dead of a coronary in December 2003 at a time when their daughter Quintana was herself in hospital dangerously ill. Didion's best-selling grief memoir about the year in which she resisted coming to terms with her partner's demise while struggling to support her daughter through a series of life-threatening conditions was published in 2005 a few months before the tragic coda of Quintana's unexpected relapse and death.

Based on the book, this one-woman show – starring Vanessa Redgrave and directed by Hare – has been developed so as to incorporate the second terrible blow.

Dressed in a simple white shirt and grey trousers, Redgrave sits on a wooden chair with her hair pulled back in a ponytail from a face that is open and beautiful in its expressive transparency. If the goal were crude physical impersonation, Redgrave would be odd casting, given that she's as tall and imposing as Didion is diminutive and bird-like. You could argue, though, that there's an awkward mismatch between the temperamental bent of the performer and the nature of the piece.

As an actress, Redgrave seems to have miraculously direct access to emotions and the brilliant ability to embrace them without inhibition. This talent is at variance with Didion's careful, calculated approach.

The writer scrutinises her descent into a kind of madness with a coolly fastidious reportorial eye and it's the resulting tensions between the poise and the raw passions held in check that give her book its compulsive readability.

On stage, you need to get the impression of a determinedly contained woman who is progressively assailed by the recognition of her own powerlessness. But there's no diffidence to be overcome in Redgrave's eager, demonstrative performance and so there's little sense of dramatic development.

Didion's denial took the form of wishful, primitive reasoning. She authorised an autopsy of John because she believed that it would show that there was something simple that could be fixed. If she could keep Quintana alive, John would come back, so it seemed to make perfect sense to hold onto his shoes.

Whether over-signalling the mischievous hope aroused by this authority-hoodwinking strategy or letting out a stricken wail at its ineffectiveness, Redgrave's Didion is too easily decipherable. It doesn't help that in the play version, the character becomes an admonitory everywoman of grief ("The details will be different, but it will happen to you. That's what I'm here to tell you").

This feels like a posture dictated by the presence of an audience rather than by anything intrinsic to material.

Bob Crowley's beautiful design consists of semi-abstract backdrops that fall to the floor as Didion sheds her illusions, but I found the play an oddly unaffecting experience.