Vingt Regards sur l'Enfant-Jésus (Twenty Contemplations on the Christ Child) was written in 1944 by Olivier Messiaen (1908–92) for his muse, subsequent wife, and dedicatee of the cycle, the pianist Yvonne Loriod. The cycle consists of twenty works of varying length for solo piano, each illustrating different mysteries of the Christ child. A complete performance takes about two hours. Vingt Regards and Messiaen's other, more frequently performed works from the 1940s – Quartet for the End of Time (1941) and the Turangalîla Symphony (1949) – between them show the composer's distinct sound worlds, eclectic influences, tonalities and harmonic invention, extraordinary rhythmic play, and lifelong fascination with birdsong. Vingt Regards, an intensely spiritual work, is the most overtly religious of the three. Messiaen gave each Contemplation a title – Contemplation of the Father, Contemplation of the Star and so forth – and followed these with more detailed descriptions on the musical and spiritual aspects of each work, guiding the performer and listener alike. This programmatic aspect of the cycle, along with recurring themes – notably the majestic Theme of God – gives it its structure. Within the score there are quite specific instructions to the performer: Leitmotifs are labelled, birdsongs identified, metronome speeds given.