It will never feel like the age of Aquarius's first dawning in 1968 when Hair delivered a liberating pro-love, anti-Vietnam war message. Yet the hippy musical still feels good. And in an era when war still rages, the first act climax with the cast standing before us naked, remains a poignant reminder of the vulnerability of the human body.
No show has a greater claim to theatrical history or social significance. But what counts here is that the superb American cast in Diane Paulus's New York production revels joyously in the spirit of the time, in some of the greatest music written for the stage by Galt MacDermot, and even manages to put flesh on one of musical theatre's flimsiest plots - a hippy gets conscripted - by Gerome Ragni and James Rado, who also wrote the lyrics.
Will Swenson's high-as-a-kite drop-out Berger, a long-haired, hilarious loose-cannon who is so loved-up its enough to make conservative America not only lock up their daughters, but their sons, mothers and fathers too.
You would have to be a curmudgeon of the highest order to resist not just the funk-soul rhythms but the touchy-feely performers who leap off the stage to deliver hugs to the audience.
But will the production appeal to a new generation of theatre-goers? A few years ago a London revival of Hair attempted an update by replacing the Vietnam war with Iraq. It did not work. This time politics are present but the emphasis is on music not message. For Hair is less a musical in the classic sense, than an anti-war gig, the driving force of which is delivered here by a terrific 12-piece on-stage band (featuring Elliott Randall, the man responsible for many a Steely Dan guitar solo) and a cast who have turned the Gielgud Theatre into a beautiful hippy be-in. (www.gielgud-theatre.com)