The character of "Xenia" is Tsar Boris' daughter in the Opera. The director wanted to spice up Boris' character and changed Xenia into one of his servants who becomes his mistress, but when wealth and luxury send her mad, she betrays him, precipitating his downfall. The producers, and especially the conductor, were so offended when they came on the set to witness Xenia depicted as a half-crazed woman living in luxury, they insisted the role be cut-down. However, since most of the role had been shot with the lead, they couldn't cut it out entirely, so the audience can catch glimpses of a young woman, looking different in every scene, hanging around Boris for no particular reason. It was not enough to tone the controversy down: the purists felt that the director meant to portray Boris as incestuous, and the producers sided with them against the director in the press, ultimately disowned the film and kept its release to a strict minimum.
Kaline Carr as Xenia is generally not mentioned in the credits, although she was widely mentioned in the press as such and is on one of the posters for the film with
Ruggero Raimondi (Boris).