In the summer of 1957, before the new musical West Side Story headed to Washington, D.C., for a pre-Broadway tryout, it was given a run-though in New York City for theater insiders. Burton Bernstein, the younger brother of Leonard Bernstein, the composer of West Side Story’s music, saw the preview and in a letter to Leonard’s wife, Felicia, assessed the show. He told her it was going to be “a large hit and [live] up to our highest expectations.” He then wrote, “The strange thing (something I’ve never experienced before) is that B. Lennuhhtt comes off as second best: the show actually is a monster ballet (a jot repetitious in spots) where no one is actually directed but choreographed instead.” B. Lennuhhtt was a nickname for his brother Leonard.

No one today would ever think that Bernstein’s contribution was second anything. His music for West Side Story, which helps transplant Romeo and Julietto the ragged west side of mid-century Manhattan, is now accepted as a brilliant sound environment created with a feel for fusion that was stunning in its time. Opera, Latin, jazz, the American songbook—all are seamlessly absorbed into a score of rhythmic virility, romantic rapture, and thrusting tonal coherence. It’s easy to cite influences—Puccini, Bizet, Stravinsky—impossible to imagine how Bernstein transcended them. But Burton Bernstein had put his finger on the pulse. The artist he deemed first best, Jerome Robbins, was the one who masterminded the idea of seamlessness, who decided that