Set in the swinging 1970s, The Hard Nut was considered a radical ballet—complete with dancing G.I. Joes and Barbies, drag performers and misbehaving adults—when it was first performed 27 years ago.

Proof of genius: the ability to create a new, old chestnut. Mark Morris' "Hard Nut" hoses all the sugar off the "Nutcracker Ballet," which has become a kind of sad industry in America, and transforms ...