Four ballets with dynamic inspiration: Stravinsky incorporated Tschaikovsky’s melodies into his poignant divertimento; the score for Tschaikovsky Pas de Deux was originally composed for Swan Lake; Peter Martins’ Bal de Couture takes its cue from stunning costumes by legendary designer Valentino; and Diamonds, the third act of Balanchine’s plotless full-length Jewels, is an homage to his Russian heritage.