Age is a major marker in John Osborne’s Look Back in Anger. Its antagonistic protagonist, Jimmy Porter, is 25, which sounds young but feels old to someone who, after a university education, is now working on a Midlands sweet stall. Jimmy despises older generations, especially Colonel Redfern, an old Raj hand, whose daughter, Alison, is married to Jimmy in a union that results as much from an affront to the English class system as the savage physical attraction that still sparks.

When it premiered in 1956, Look Back in Anger also became the play that defined an age, with Jimmy acclaimed as the rebellious, contemptuous voice of a generation, or at least the men, who were, at that time, the only sound heard socially and politically. Now the play is itself part of a far past, the Derby Playhouse, which rejected the script before the Royal Court made it famous, invites us, in a Golden Jubilee revival, to see how well the play has aged.

Look Back in Anger is a harder play to celebrate than, say, Stoppard’s Rosencrantz and Guildenstern are Dead, 50 this summer, or Pinter’s The Birthday Party, 60 in two years. Time has been unkind to Jimmy’s signature tirades against the state of England and its women, which now seem both disgustingly misogynistic and long-winded.