Contrary to popular belief, the cast of Hair, the great hippie-rock musical that opened on Broadway a quarter century ago this week, were shy about doffing their duds for the show's notorious nude finale. ''At first, maybe two or three did, then more and more,'' composer Galt MacDermot recalls of the big strip-in. ''I think they got paid a little more if they did. I never saw [cast member] Diane Keaton do it, though.''
Also contrary to general belief, Hair wasn't an instant hit. Only in 1969, after the California production opened, did its tunes take over the pop charts: the Fifth Dimension's ''Aquarius/Let the Sunshine In'' at No. 1, the Cowsills' ''Hair'' at No. 2. There was even an album of songs snipped from the show, DisinHAIRited.
But in the long run, Hair made more than $80 million and had productions all over the globe, usually with local actors (though the Las Vegas cast was flown in from Hawaii because, said the apologetic director, ''there just aren't any young people in Vegas''). During the finale of a 1969 London performance, the AP reported, Princess Anne ''broke into a hip-swinging routine, flinging her arms in abandon.'' In Japan, such tunes as ''Hashish'' and ''Sodomy'' were pronounced ''very philosophical'' by the brother of the emperor. Ironically, Hair was banned in South Africa, although the Cape Town- raised MacDermot says its structure was partly inspired by the Zulu theater tradition of blending song, dance, and speech.
For the past 15 years Hair has continuously toured Europe. ''A couple of days ago [lyricist] Jim Rado and I went to London to talk about putting it on in the Old Vic,'' says MacDermot. ''We may yet [bring it back] to Broadway.'' (They're also hawking their musical Sun, a sort of Hair for environmentalists.) Two months ago, Hair premiered in Sarajevo, where ''Easy to Be Hard'' resonated as an indictment of ethnic cleansing. MacDermot says war was always on the minds of the show's creators. ''There's that chant, 'Ripped open by metal explosion' It's about a guy about to be drafted. Will he go to Vietnam and die? Or pull a Clinton?''
But while Hair's mystic crystal revelations are eternal, a few of its references are not. One young cast member in a 1988 Chicago Hair revival turned to the director quizzically and asked, ''Excuse me, but exactly who was Timothy Leary?''