This selection is from the third film in the Harry Potter franchise, HP and the Prisoner of Azkaban. It’s performed by the Frog Choir, a group of Hogwarts students who don’t appear in any of the actual books but whom J. K. Rowling really loved when she saw them in the movie. They perform at the welcoming feast that begins the new school term and each carries a toad, one of which croaks during the song. (Why aren’t they called the Toad Choir? I don’t know.) The music is, of course, by John Williams. Isn’t everything?