Hair is a musical that doesn't have very well-defined dance numbers. Yes, there are big songs and dances, but at the Town Hall Arts Center, the entire production was a swaying, shimmying, surging celebration, with action and music so intertwined that director/choreographer Nick Sugar must have found both his roles merging into one. His fine cast brought Hair into the present while maintaining the ethos of the hippie '60s — easy sex, casual nudity, idealistic ideas and rebellious romances between black and white that were highly unusual in those racially tense years. Sugar's smart, sexy choreography, along with the exuberant musical direction of Donna Kolpan Debreceni, made for a transcendent evening.