The musical, which featured such songs as "Aquarius," "Easy to Be Hard," "Frank Mills," "Walking in Space" and "Good Morning Starshine," was created by Gerome Ragni and James Rado (book and lyrics) and Galt MacDermot (music). Liz Smith reports that co-lyricist/co-librettist Rado and his brother Ted Rado have created a sequel to the famed musical. Currently titled Billy Earth, the musical begins where Hair ended, at the death of the central character Claude (James Rado played Claude in the original Broadway run). The 38-song proposal for Billy Earth, according to the gossip columnist, is "already in the hands of a Broadway producer."

Hair focused on a group of hippies — called The Tribe — in New York City in the late 1960's, and gives voice to their passions and frustrations in loose scenes and interactions, including a rant against war, an embrace of free love (including a group nude scene) and odes to nature, life, drugs and multiculturalism. Heather MacRae, Melba Moore, Keith Carradine and Joe Morton were among performers in the early Broadway run of the show.