Hair: The American Tribal Love-Rock Musical debuted on Broadway in 1968, going against the grain of traditional musicals by telling the story of a group of hippies -- complete with drug use, nudity and a rock score.

It was a smash hit, even with all the controversy it stirred, running for 1,750 performances before it closed in 1972.

The show wasn't just a success on the Great White Way. Four recordings of Galt MacDermot's songs from the musical -- the Cowsills' take on the title track, Oliver's "Good Morning Starshine," Three Dog Night's "Easy to Be Hard" and the 5th Dimension's medley of "Aquarius" and "Let the Sunshine In" -- all reached the Top 5 in 1969, with the 5th Dimension hitting No. 1 and winning a Record of the Year Grammy.

Seven years later, Milos Forman turned Hair into a movie, with choreography by Twyla Tharp. The film, without the stage show's subtitle, opened on March 14, 1979. But it also underwent several changes in its adaptation that reportedly upset the book writers and original Broadway stars Gerome Ragni and James Rado.

Hair was perfect for the late '60s. It's about a tribe of New York hippies -- including Claude, Berger and Sheila -- that touch on all aspects of the counterculture, including free love ("Sodomy"), drugs, racism ("Colored Spade"), anti-war sentiments and the ecology movements.

Overall, as related in the title song, it's a look at society's unwillingness to accept hippies for who they are. Throughout the story, Claude questions whether or not to dodge the draft as others have done. By the end, he decides to go to Vietnam, where he's killed.

For the big-screen adaptation, Michael Weller adapted the book and made a few changes, such as having Claude (played by John Savage) be a native of Oklahoma who lands in New York to join the military and gets befriended by the hippies. And Sheila (Beverly D'Angelo) now came from a wealthy family and joined the tribe after meeting Claude.

Several songs were removed or cut for time and were occasionally sung by different characters than they were in the musical. Working with a bigger budget, MacDermot arranged some songs differently, evolving them from a small jazz-rock combo to incorporate big balladry ("My Conviction") and disco ("Aquarius"). MacDermot also wrote a new song, the country-infused "Somebody to Love," heard in the background.

Watch a Scene From 'Hair'

If those and other changes were necessary to shore up the plot for the movie -- a common critique of the musical was the looseness of its story -- what Weller did to the ending wasn't. Claude still goes into the Army, but when his friends visit him during basic training, Berger (Treat Williams) winds up dressing up as Claude to allow him to spend time with Sheila. But before Claude could return to the base, Berger is shipped out and killed in action.

Even though Ragni and Rado were unhappy with the results, The New York Times' movie critic Vincent Canby thought the changes improved the story. He called it a "rollicking musical memoir, as much a recollection of the show as of the period, a film that has the charm of a fable and the slickness of Broadway show biz at its breathless best.

"Mr. Weller's inventions make this Hair seem much funnier than I remember the show's having been," he continued. "They also provide time and space for the development of characters who, on the stage, had to express themselves almost entirely in song."

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