The mysterious visitor whose presence provokes a moral crisis in a middle-class family is a familiar theatrical device, one JB Priestley popularised in An Inspector Calls. Cordelia Lynn gives it a new twist by setting her play in a London pulverised by a bomb attack that has left hundreds dead. But while Lynn – winner of the Royal Court’s annual Harold Pinter commission financed by his estate – shows promise, she could learn from her benefactor’s dramatic economy.
Lynn starts by showing the impassioned Imogen joining a hashtag campaign offering sanctuary to those caught up in the bombing. Her parents are unnerved by her impetuosity while her younger sister, Chloe, is strangely excited. When John duly knocks at their door, he turns out to be a mechanical engineering student understandably in a state of shock. John’s guarded taciturnity, uncertain origins and steadfast refusal to shed his coat leaves the family, and us, unsure if he is a victim of the bombing or possibly one of its perpetrators.
The play picks off an easy target in attacking the parents’ shallow liberalism and overindulges the daughters in their self-explorations. But Lynn also generates considerable tension, shows how a crisis exacerbates the generation gap and raises the big issue of whether attacks on our way of life are, as Imogen asserts, “the aftermath of our harvest”.
James Macdonald’s Theatre Upstairs production shows his customary sure-footedness. Irfan Shamji invests John with a rare stillness, and there is good work by Pearl Chanda and Kitty Archer as the voluble daughters and Sarah Woodward and Neil Dudgeon as their nervous parents. Even if the play could do with editing, I felt I was in the presence of a real dramatist.
• At the Royal Court, London, until 11 August. Box office: 020-7565 5000.