After more than 40 years, Hair, the rock musical that hit the zeitgeist in 1968 returns to the West End, inviting us to “turn off, tune in, drop out” and welcome the dawning of the Age of Aquarius.

New York Public Theater’s vibrant production has the hippie tribe clambering over the audience, stripping off, and sporting the iconic long hair, Afros and psychedelic kaftans of the pre-Aids era as these Greenwich Village objectors to the Vietnam War celebrate free love, sex, and getting stoned.

It no longer shocks and the thin plot still rambles, but with its great songs, powerfully poignant pacifist message and Will Swenson’s recklessly atavistic Berger finding it Easy To Be Hard, this exuberant nostalgia trip really does Let the Sunshine In.

» Gielgud, Shaftesbury Ave, W1D 6AR  Piccadilly Circus (0844 482 5130; Booking until Jan 8, 2011. £17.50-£65