Nick Payne’s short, intense play Elegy, currently playing at the Donmar Warehouse, is undoubtedly clever and thought-provoking, but it left me feeling curiously underwhelmed.

The acting, from its three protagonists, particularly Zoe Wanamaker as Lorna, a late middle-aged woman suffering from a nameless brain-debilitating disease very much like dementia, is superb.  But I wondered if it wasn’t so much a play as a cleverly staged and very interesting philosophical debate on how memories define our identity.

The premise is promising: a futuristic world in which it is possible to replace damaged parts of someone’s brain at the cost of large chunks of his or her memory.  Lorna’s disease will kill her unless she undertakes such a procedure.  But undergoing the operation will erase all memories of her relationship with her wife Carrie, played by Barbara Flynn.

We first meet the two women after Lorna has had the life-saving procedure.  “What does it feel like, not having a piece of your life?” Carrie asks.  Lorna’s answer, delivered in a matter-of-fact, emotionless way, reveals the cost she (and Carrie) have paid for her survival.  She is no longer the woman she was, the woman Carrie loved.  Or is she?

The huge question of what constitutes an individual’s identity is thus posed at the outset, before we, the audience, are even properly aware of what’s going on.  “I miss loving you,” says the tormented Carrie.  “It’s as if you are dead”.

This is all very sad and not a little confusing when uttered so early in the play.  It is a mark of the skills of all three actors – Nina Sosanya gives a faultless depiction of a first-class doctor with zero emotional empathy – that they carry us with them at all, for the play never really develops beyond a soul-searching reflection on how our memories define who we are, and ends with the same few minutes of dialogue that it began, now rendered more understandable though no less uncomfortable to watch.

Dementia, of course, is a bit like this.  There are no clear answers.  But Elegy isn’t life, it’s art; it’s a play and, answers or not, I think it needed more flesh on its bones.

Zoe Wanamaker’s portrayal of Lorna hints at the mischievous, sparky little thing she once was (and still is to a certain extent before her operation), while Carrie seems a more solid, dependable type.   That’s really all we’re given and I’d like to have known more about their relationship, the little details that made it what it was.  I’d like the people to have been brought to life as much as the ideas were.

Beyond the fact that the two women were both teachers who first met in church and that they couldn’t agree on the readings at their wedding, we know very little about them.  They met, they loved and now, at least for Lorna, that love has gone.  The couple’s ultimately riven relationship is symbolised on Tom Scutt’s simple stage set by a tree trunk, split in two.

It’s almost as if, having posed the big questions at the outset, the play’s great potential is never fulfilled and we merely turn full circle.

Perhaps I’m being unfair and it is because I am now so immersed in the world of dementia, of memories lost, of relationships and identities that are challenged and changed, that I expect too much of an hour-long play.  But just as, at the heart of any discussion of dementia is the person affected by it and his or her loved ones, at the heart of this play, surely, are its characters, and I’m just not sure I knew who they really were.