 His first horror film, "Malenka, The Vampire's Niece" (1969), was written to be a psychological thriller about a young woman who inherits a castle in Europe and is summarily driven crazy by her uncle who tries to convince her that he and she are both vampires.At the end of the film, the uncle's scheme is revealed and explained by her boyfriend to be a hoax.However, after de Ossorio finished the film, the producers decided to make the uncle an actual vampire in the English-language version, and added a low-budget disintegration scene to the finale of the English-dubbed prints that completely contradicted the plot.