In 1967, at the age of 38, he wrote the music for the groundbreaking show Hair. The show was such a hit in Canada that the Toronto production, at the Royal Alexandra Theatre, grossed over $1-million in the first 3 months. Following the success of Hair, MacDermot adapted his score for the big screen and teamed up with veteran director Milos Forman to bring the popular and controversial musical to life.
Establishing a new style for musicals and spawning several imitators, Hair reflected the concerns of the hippie culture in North America during the 1960s. Hair received a Grammy composer’s award in 1968 for best score from an original-cast show album. A medley of Aquarius/Let the Sunshine In was a major hit in 1969 as recorded by the Fifth Dimension.