Born in Essen, the son of architect
Horst Loy and a translator, Loy began studies of opera directing at the Folkwangschule with Dieter Bülter-Marell at the age of 14. He received the Folkwang-Preis award for his first staged work, Pimpinone. He studied in Essen until 1982 and continued his studies at the Munich University, including science of the theatre, art history, and Italian studies. In 1984, Loy began work as an assistant at the Musiktheater im Revier, where he collaborated with
Dietrich Hilsdorf and
Jaroslav Chundela , among others. In 1986, he moved to the Staatstheater Wiesbaden, and since 1990 he has worked as a freelance director.
He made his debut at the Royal Opera House in 2002 with Ariadne auf Naxos, conducted by Antonio Pappano who was then the new music director. He also staged there Donizetti's Lucia di Lammermoor, Alban Berg's Lulu and Wagner's Tristan und Isolde. He directed Mussorgski's Khovanshchina at the Dutch National Opera, Handel's Alcina and Bellini's I Capuleti e i Montecchi at the Opernhaus Zürich, Verdi's Macbeth at the Grand Théâtre de Genève, Britten's Peter Grimes at the Theater an der Wien, Janáček's Jenůfa at the Deutsche Oper Berlin, Der Rosenkavalier by Richard Strauss at the Royal Swedish Opera, Mozart's Così fan tutte and Don Giovanni, and Arabella by Richard Strauss at the Frankfurt Opera, his Daphne at the Theater Basel, and Handel's Theodora for the Salzburg Festival. In 2017, he directed the premiere of Andrea Lorenzo Scartazzini's Edward II. at the Deutsche Oper Berlin.
Among other awards, his staging of Mozart's Così fan tutte at the Frankfurt Opera earned him the prize Der Faust in the category direction in music theatre (Regie Musiktheater) in 2008.