Maria Friderike Radner (7 May 1981 – 24 March 2015) was a German contralto and internationally renowned opera singer. After studying at the Robert Schumann Hochschule in Düsseldorf, she appeared internationally in opera and concert. In January 2013, she played the Schwertleite in "Die Walküre" at the Teatro Comunale Florence, Italy under Zubin Mehta, and in March the Erda at the Grand Théâtre de Genève, conducted by Ingo Metzmacher. Her debut at the Metropolitan Opera in 2012 in "Götterdämmerung" was part of the documentation of the production in the film "Wagner's Dream".