I have a confession to make: On July 1^st, I went to see Skylight, the play by David Hare that has been performing at Wyndham’s Theatre this summer, and have been meaning to write about it ever since!  Sic transit gloria aestatis!  It stars Carey Mulligan and Bill Nighy – and in fact, apart from two short appearances by Matthew Beard as Nighy’s son Edward, they have the stage to themselves for the whole two-hour performance, which must require considerable stamina, especially as both play their characters with enormous energy and verve.

First performed in 1995, Skylight tells the story of an extra-marital affair between Tom Sergeant (Nighy) and Kyra Hollis (Mulligan) that draws to an abrupt close after Tom’s wife Alice finds out.  The termination is at Kyra’s insistence, not Alice’s; but reconciliation is made virtually impossible for Tom after Alice develops a terminal illness shortly afterwards.  He nurses her until she dies, an event taking place some time before the action of the play.  Kyra, who somewhat implausibly had not only been working for Tom’s business but also sharing his and Alice’s house, leaves precipitately, trains as a teacher and builds a new life for herself teaching deprived children in a run-down part of London.  Her flat, in another bleak London borough, is a long journey from the school where she works.  The action takes place just before Christmas.  The flat is cold and it is snowing.  Edward appears unexpectedly out of the blue to tell Kyra of his mother’s death.  He appears not to know why she ceased to live with his family.

A few hours after Edward’s departure, just after Kyra has taken a bath in an attempt to get warm, Tom shows up.  He gives more details about Alice’s death, but the real reason for his visit is to try to find out why Kyra abandoned him and perhaps – though he does not state this explicitly – to persuade her to return to him.  Kyra treats him warily and with irony, though a certain fondness begins to creep through.  At first, the audience is entirely on her side.  Tom comes across as a self-centred self-apologist who believes that his money can usually get him what he wants.  He is disparaging about Kyra’s job, her pupils, her lifestyle and her Spartan flat.  However, the genius of the play lies in the fact that the emphasis then gradually shifts to reveal Kyra’s shortcomings, as well as Tom’s.  This yo-yoing of sympathy for one or the other character happens more rapidly as the play goes on.  The conceits, the posturing, some element of lying or at least disregard for the truth and, through it all, the essential decency of both Kyra and Tom are exposed as the two actors deliver David Hare’s sparkling lines with convincing vehemence and wit.  The onlooker hopes against hope that they will revive their relationship.

Skylight is a miracle of good casting.  Kyra is older, more sophisticated and less waif-like than the Jenny of An Education, yet Mulligan’s performance shows something of the obstinate naiveté and acceptance of face values at odds with reality that she created in the earlier role.  Nighy’s depiction of Tom is unlike any other role that I have seen him play, though Tom’s wit, his irony, his rather louche outlook on life and the sense of melancholy vying with humour are all Nighy trademarks.  Throughout the whole performance, the actors create with consummate skill the presence of an invisible third character – Alice, for whom Tom made a skylight when she was lying in bed, too ill to look out of a conventional window.  Perhaps it is Alice who triumphs in the end.

When I attended the performance on July 1^st, the theatre was packed.  I’m not sure if tickets are available for the remaining few performances before the play closes, but if you are able to get hold of one, snatch at the opportunity – plays of this calibre are rare indeed, even in the West End!

Wyndham’s Theatre, Charing Cross Road

• An Education Bill Nighy Carey Mulligan David Hare Skylight Wyndham's Theatre