There’s a class of drama in which baffled, alienated characters go on walkabout to discover their own and life’s meaning: the oppressed businessman who gives Mamet’s Edmond its title, the New York protagonists of Howard Korder’s Lights, and now Harper Regan in Simon Stephens’s play of that name. She leaves her job, her family and her Uxbridge home to visit her dying father in Manchester, arrives too late, glasses an antiSemite in a bar, sleeps with a stranger she has contacted on the internet, has a fierce contretemps with the mother she dislikes – and returns home a bit more self-knowing than when she left.

This gives the excellent Lesley Sharp, who plays Harper, plenty of opportunities to display her ability to be sweet, naive, apologetic, angry, despairing and much else. But for the first half this isn’t quite enough to sustain a meandering narrative. Indeed, it’s only after the interval that Stephens reveals the problem afflicting a family that Harper professes to think nice and normal; and, since it’s guessable, I’m going to reveal it here. Her kindly husband, Nick Sidi’s Seth, is on the sex offenders register, having taken a series of photos of little girls in a park.

Actually, Stephens might have revealed this secret before, since it explains Harper’s confusion, increases the play’s tension and ups the dramatic stakes. As it is, his purpose becomes apparent only gradually. Harper blames her mother because she wrongly thinks the old lady forced the father she adored to reject Seth, whom she wants and tries to believe innocent. Similarly, her own adolescent daughter, Jessica Raine’s Sarah, won’t face the truth about her own father and resents Harper when she herself does so. The play, then, is about the lure of wishfulness, lies, prejudices and the need to acknowledge even painful facts.

Harper’s obsessive curiosity about everything brings some good, offbeat writing out of Stephens, especially in scenes in which the woman stalks and quizzes a puzzled black student nicely played by Troy Glasgow. But there are plenty of other quirky moments in Marianne Elliott’s production, some involving Michael Mears as Harper’s nerdish yet sinister boss, others Susan Brown as her mother, a prissy Alan Bennett northerner who asks the play’s basic question. Has she squandered her life on pointlessness? Yes – and maybe many of us do the same.

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