“Boléro” is among the most lucrative works of classical music

M “Boléro” is a strange piece of music, consisting of two melodies repeated nine times each. Originally the score to a ballet, it is catchy and keeps running in the listener’s head long after it ends. “Boléro”, a new French biopic about Ravel’s struggle to compose the work in 1928, also employs repetition. Anne Fontaine, the director and co-writer, returns to Ravel’s tortured sexuality, fascination with mechanical noise and slow mental deterioration. He died in 1937 of a brain disease; neurologists think it may have been frontotemporal dementia, which is...