The beloved VAMPIRE SISTERS are back! This time they have a new baby brother, Franz, a sweet half-vampire. But he is in danger!
The evil vampire queen Antanasia wants him in her castle, as her heir. When Silvania accidentally hypnotizes her parents Mihai and Elvira, thus putting them temporarily out of action, Antanasia kidnaps baby Franz. Daka pursues her to Transylvania to rescue him. With Murdo's help she breaks into the castle, but is, instead, captivated by Antanasia because she is living what Daka has always dreamed of, the life of a free vampire! Meanwhile Silvania and Dirk van Kombast are on their way to the castle. Together with Murdo they have to free Franz and Daka from Antanasia's clutches before Franz is crowned successor to the throne.