This German drama tells the story of a musician who is killed and leaves his work unfinished. His apprentice is cleared of the murder and turns out to be the real composer.

A German scientist murders his fiancée during World War II when he learns that she has been selling the results of his secret research to the enemy.

Baron Franz von Naydek is constantly being mistaken for Prince Woronzeff, since both look identical. One day, Woronzeff decides that this similarity might come in handy. Since he is very ill and can no longer deal with the intrigues of his relatives, he begs his friend Naydek to play the role of prince for a while. Naydek agrees and everything seems to be going splendidly. Woronzeff’s ex-nag Diane sees through the game, however, but says nothing, since she’s fallen for Naydek. He, in turn, has the hots for Nadja, Woronzeff’s daughter, long thought lost and who has now reappeared. The prince’s relatives fear for their inheritance and so refuse to acknowledge Nadja’s existence. In the interim, Woronzeff dies. Now Naydek is obliged to play the role for a much longer time than he bargained for.

French aristocrat falls for Russian nightclub singer, gets involved in underground Russian revolutionary movement. Parts 1 and 2 were re-edited in the only surviving copy named Daughter of the Night.