Frau Schmidt is the "fuhrer" of "Canada," a kind of shop within the camp reserved for the camp elite. Schmidt has been a prisoner for many years, but it is unclear why she has been interred. There is speculation that she may have been a Communist or the owner of a brothel.
Schmidt is cold and calculating. She treats the Jewish prisoners with contempt. Her true character is revealed toward the end of the book, when Alma gains her release. Schmidt, who has been petitioning for her own release for years, is consumed with envy and hatred, but fools Alma into thinking that she is her friend. She invites Alma to a farewell dinner and poisons her.
Schmidt is an example of the ruthlessness of the camps. In the same way that the beauty of the music the prisoners play is perversely juxtaposed with the forced labor of the prisoners, Schmidt's cool exterior conceals a murderer.