Water Lilies: Reflection of Willows was one of a set of 25 Monet paintings in a huge collection of Western art acquired by the Japanese collector Kōjirō Matsukata. In the leadup to World War II, he had the works stored for safekeeping in France and England. When they were finally returned to Japan in 1959 (after Matsukata’s death), this work wasn’t among them. Now it has turned up, though it’s badly damaged.