This is perhaps Grieg's most famous composition, and comes from the first Peer Gynt suite. It was originally a piece of incidental music to accompany the scene in Ibsen's play where Peer ventures into the Mountain King's hall, finding himself surrounded by trolls, gnomes and goblins chanting 'slay him!'. It starts with a slow and sinister melody on the alto flute that repeats through all the parts, building to a thrilling climax . It is also famous as the music from the Alton Towers adverts!