Florence Foster Jenkins is known as "the worst singer of all times" and yet she is a cult figure whose recordings still outsell many contemporary singers. Opera superstar Joyce DiDonato interprets the flamboyant "queen of dissonance". The involvement of the celebrated virtuoso makes it possible to contrast two different musical perspectives and gives viewers a vivid impression of the film's key conflict between inner delusion and external reality.

Joyce DiDonato
as Florence Foster Jenkins

Adam Benzwi
as Cosme McMoon

Lars-Peter Schmädicke
as St. Clair Bayfield

Jasmin Antic
as Kathleen Bayfield

Manuel Palazzo
as Adolph Pollitz

Gregor Benko
as Self

April Woodall
as Self

Kevin Clarke
as Self

Davie Lerner
as Self

Gino Francesconi
as Self