'L'Orfeo is an opera about opera. It's an opera about the power of music. It's about the power of art to construct the world," says director and artist William Kentridge. Claudio Monteverdi's 1607 work is, if not quite the first ever opera, the earliest opera still performed today, written when the form was in its very infancy. Monteverdi called his work – composed for performance at the ducal court of Mantua, a "favola in musica – legend in music".