The opera is scheduled to premiere in the fall of 2007; Peter Mussbach, the company's general manager and artistic director, will direct. The libretto is by Christian Lehnert, a German poet.
In Greek mythology, Phaedra is the wife of Theseus, the hero and founding king of Athens. She falls in love with her stepson, Hippolytus; after he rejects her, she commits suicide, leaving a note that falsely accuses him of rape. An angry Theseus curses Hippolytus, who is killed. The story appears in Euripides' Hippolytus and Phdre, by the 17th-century French playwright Jean Racine.
Henze's 15 previous operas include The Stag King, Boulevard Solitude, The Bassarids, We Come to the River, Venus and Adonis, and L'Upupa und der Triumph der Sohnesliebe. When the latter premiered in 2003, Henze said that it would be his last opera.