The musical Hair has a privileged place in American culture. Its songs, particularly classics like “Aquarius,” “Good Morning Starshine,” and “Let the Sun Shine In,” are deeply familiar, an inescapable part of the soundtrack of American life in the second half of the twentieth century. Lots of people have seen Milos Forman’s 1979 filmed version. How many, though, have seen the musical itself? It opened at the Public Theater in 1967, subsequently moving to Broadway’s Biltmore Theater where it played for four years; therefore only people well launched in middle age, at the very least, can have seen the original production; regional, stock, and amateur productions are few and far between. We know Hair more as what we think it stands for—peace, love, joy, free love—than for the darker and more disturbing drama it actually presents.

Seeing the full-scale revival ...