According to prophesy, the noble House of de Berghman will end as it began, in murder. Fratricide, to be precise, with a brother slain by his younger sibling. So, when his wife gives birth to twin boys (Gregor and Anton), Baron de Berghman takes the precaution of walling up the room in which the murder will supposedly take place: the Black Room. Several decades later, Gregor, now the despised Baron, comes up with his own drastic but beautifully simple scheme to cheat the prophesy... The good-and-evil twins plotline has been done to death of course - it probably already had by 1935 - but this one is hard to beat for entertainment. The production isn't quite first-class but Karloff is brilliant, essentially playing three parts here: wicked Gregor, kindly Anton, and wicked-Gregor-masquerading-as-kindly-Anton. Though the plot is full of holes (for instance, wouldn't it have been safest to have demolished the Black Room?) and the script has the annoying habit of stating the obvious, this is still great fun.