While a disappointment at the box office, Hair is noteworthy for several reasons, chief among them the fact that it is a surprisingly good adaptation of a play that should have defied translation to the screen. Working with screenwriter Michael Weller, director Milos Forman has taken what on-stage was an atmospheric period piece with no discernible plot and created a coherent story with considerable emotional impact. The talented ensemble cast is of enormous help, especially Treat Williams, John Savage, and Beverly D'Angelo, but what makes the movie is Galt MacDermot's dazzling score -- and choreographer Twyla Tharp's and Forman's interpretation of it. From the camera's dizzying sweep around Ren Woods as she sings "Aquarius" to Savage's drug-induced wedding ballet to the crowded masses surrounding Savage in "Where Do I Go," the songs are staged with that rare combination of confidence and vitality that always mark the best moments in musical films. The sketchiness with which the characters are drawn, a problem arising from the large number of characters and compounded by lyrics that are more pop- than character-driven, damages the film, and many do not respond to its "take" on the 1960s, but overall Hair is a worthwhile and enjoyable film.