The brain and identity have been the subject of some brilliant work recently, not least Nick Payne's Incognito, in which the main protagonist was a man who was tragically unable to remember the recent past.

Peter Quilter's hospital-set new play takes a different, but equally promising tack. Instead of being unable to remember events and conversations that are minutes old, Quilter's hero Michael, played here by Alistair McGowan, wakes from a three-week brain clot-induced coma to find that he has lost all memory of the previous 11 years. When his domineering mother Carol (Maggie Ollerenshaw) discovers that he isn't in the here-and-now but back in post-9/11 and pre-7/7 world of 2005 the scene is set, it seems, for an interesting dramatic investigation.

News footage silently plays on the TV screen in Michael's hospital room, where all the action takes place. And for a while it appears that Quilter's play is gearing up to explore the effect that world events have on an individual's (and the collective) psyche. Could the past 10 years of terrorism, war and raging epidemic have had a collectively depressing effect, one that it is only possible to escape if you've had the slate wiped clean?

But it turns out that Quilter is less interested in the effect that memory loss has on the amnesiac than the people around him. This is also a potentially interesting avenue, but here it's defined by something much more conventional. A dialogue of bitter resentment between the two people who love Michael most - mother Carol and Michael's lover of the previous ten years, Paul (Daniel Weyman) of whom Michael has no memory and who Carol blames for making her brilliant, artistic son dull.

As the two vie for Michael's affections, the patient looks on with world-weary bemusement, as well he might. Because, instead of being at the centre of an adventure about how a damaged brain affects the mind, revealing the pluses and minuses and the neurological quirks - an area hinted at in passing when Michael refers to Oliver Sacks's famous case study about the man who mistook his wife for a hat, though dismissed with the line "I have no wife and no hat" - Michael instead finds that he is the subject and prize of a much less interesting tug-of-war.

Dramatically, this a pedestrian approach. There is no attempt here to reflect what memory loss actually feels like, nor does Quilter's writing seek to represent the rush and confusion of its return.

McGowan delivers a beautifully nuanced, subtly camp performance. But a bit like the 4,000 days of Michael's lost decade, the two hours of this play feel like a lost opportunity.