Take the exuberant, dark-hued chaos of Maurice Sendak’s classic children’s picture books, add the glittering sonic fantasy of the British composer Oliver Knussen, and the result is a double-bill like nothing else in modern opera. Higglety, Pigglety, Pop! takes a dog called Jennie on a journey into wonderland, while Where the Wild Things Are follows the mischievous Max into a nocturnal world where mayhem isn’t just allowed—it’s the law. Knussen’s imagination runs wild, too, in music that’s as original as it is entertaining: flamboyant, funny, tender, and utterly unexpected. The composer himself conducts this studio recording (the first of the complete double-bill). With pitch-perfect playing by the London Sinfonietta, it’s the definitive recording of a pair of operas that continue to delight and thrill listeners of all ages.