William Lewis tried himself as an athlete and as a writer before having his voice trained. He made his debut in 1953 as Rinuccio in Fort Worth. He sang around the US for the next few years (Dallas, Santa Fe, San Francisco, Cincinnati, Pittsburgh, Hawaii, San Antonio, Tulsa, New York City Opera). In 1958, he was at the Met for the first time (debut role: Narraboth). At that house, he was a fixture from 1972 to 1989, and sang for the last time in 1992 – a total of 234 performances, and an amazing variety of roles: Rodolfo, Andres, Ägisth, Cassio, Roméo, German, Macduff, Don José, Pinkerton, Hélénus (Les Troyens), Melot, Gabriele Adorno, Arrigo, Tambourmajor, Števa, Turiddu, Grigorij, Cavaradossi, Alfredo, Alwa (Lulu by Berg), Erik, Oedipus rex, Idomeneo, Chevalier de la Force (Dialogues des Carmélites by Poulenc), Jimmy Mahoney (Aufstieg und Fall der Stadt Mahagonny), Malatestino (Francesca da Rimini), Hoffmann, Golitsyn (Khovanshchina), Red Whiskers (Billy Budd), Walther von der Vogelweide, Tannhäuser.