As you arrive, people on stage chat, chill, get a buzz cut (virtually) or sing along to hip-hop. Clearly, some are spectators, in impromptu improv, but it’s unclear which. That’s the point. In Inua Ellams’s enlightening and lively play, the line between audience and actors is thin. The scenes are set in barber shops in Harare, Kampala, Lagos, Accra, Johannesburg and London. Characters recur, from a boy who must look smart for an interview (Demmy Ladipo) to a kindly head barber (Anthony Ofoegbu). Funny, touching narrative strands intertwine. The similarities are striking: the same music playing, the same jokes told, the same football match on the box. And all the characters delight in reverse Samson syndrome: their hair shorn, they walk out twice the man they were. There’s a lot about fathers here, the absent, the violent, the ultimately disappointing. But most, perhaps too many, of the men who actually appear are likeable. There’s oddly little swearing. Nevertheless, Ellams has created a vital play that gives this entirely black male cast countless chances to shine, which they largely seize.