Ludwig von Beethoven was a Romantic-era composer of classical music. The book suggests that Beethoven made a deal with the devil—with Luc—in exchange for fame and success. In 1827, Luc transports himself and Addie to Beethoven’s chamber and, ignoring Beethoven’s pleading, transforms into a dark, monstrous creature and horrifically steals Beethoven’s soul. Luc’s ferocious act reminds Addie, who has recently grown bolder around Luc, that Luc is a fearsome, cruel god who can destroy her if he wants to.