Revealing mistake: The cake Mildred lifts is obviously a solid prop as the "frosting" does not smear her dress when she holds it close to her body.
Revealing mistake: The wide shot of the exterior of Drearcliffe House is a recycling of the wide shot of the church where Meade and his Nazi colleagues were hiding in "Sherlock Holmes and the Voice of Terror." It can't be the same place, as the mansion is located in Scotland and the church in England. (00:01:21)