Sally Cookson’s Peter Pan at the National Theatre is an exuberant steampunk pyjama party, exploring grown-up themes of abandonment, jeopardy, loneliness and despair. Cookson thrusts Wendy Darling (Madeleine Worral) centre-stage, as her story arcs from wonder to understanding and impending adulthood, while Paul Hilton’s petulant Peter, in his outgrown green suit and arrested adolescence, remains...