Sir Karell Borotyn, a renowned scholar and philanthropist, was found dead in his home by the local village. The police suspect Count Mora, a vampire believed to haunt the area, as the killer. However, it is revealed that Sir Karell was actually killed by a different individual.
Professor Zelen, an expert on vampires, has been sent in to investigate the case and prevent Irena, Sir Karell's daughter, from being targeted. As Professor Zelen delves deeper into the investigation, he uncovers secrets surrounding Sir Karell's death. It turns out that he had been working on a secret project for years, and his death was not an accident.
The professor discovers that Sir Karell had been working with a group of scientists to create a cure for vampires. However, their research went awry, and they accidentally created a virus that could turn humans into vampires. This discovery leads to further revelations about the circumstances of Sir Karell's death.
It turns out that the count had been monitoring the research for years, and when he discovered the virus, he knew he needed to eliminate the source of the problem. He set up a trap for Professor Zelen and Irena, intending to kill them both. However, the professor managed to escape and alerted the authorities.
As the story unfolds, Professor Zelen and Irena must work together to uncover the truth and stop the count before he can cause any more harm. With their combined knowledge and expertise, they stand a chance of saving the world from the threat of vampires once and for all.