Images of Thanatos, or death, appear in Prokofiev’s output in a variety of contexts. Thoughts of death threw many shadows over the young composer, despite his naturally happy disposition; but from the 1920s, as a Christian Scientist, he tried to see death as merely a human aberration. His musical works are nonetheless full of death images. Different cultural-historical traditions are drawn upon, reflecting his own life experiences. Ancient mythological and magical beliefs, as well as Christian motives, rub shoulders with positivism and with interpretations of Bolshevism as a secular religion. By exploring concepts of Thanatos in a wide range of Prokofiev’s theater works—from Maddalena, Chout, and The Fiery Angel to Semyon Kotko, Romeo and Juliet, and War and Peace—this chapter casts new light on the composer’s emotional attitudes toward the mysteries of death, as well as revealing special psychological depths in his musical ideas.