De temporum fine comoedia ("Mystery on the End of Time") is a large-scale work for many soloists, several dramatic actors, a choir, and a huge orchestra with about thirty percussion instruments. Throughout his life Orff was developing a special type of musical theatre where he synthesized relatively simple musical forms, allegedly unprofessional singing, dance, dramatic acting and recitation in search of the art's proto-language. He called such synthesis the "world theatre", omitting the very word "music", although it is music that plays a crucial part in his mysteries. Orff was creating De temporum fine comoedia for ten years and edited it repeatedly. The 1981 version will be performed at the closing ceremony of the Diaghilev Festival. The production is directed by Anna Guseva, the musical director and conductor is Teodor Currentzis.