Halloween: Ghostly Goings-On at the Harry Potter Studio Tour
Time Out says
There are special – and mostly thoroughly repulsive – additions to the Making of Harry Potter Tour at Warner Bros Studio for Halloween. The Great Hall will be decked as it was for the Halloween feast in 'Harry Potter and the Prisoner of Azkaban' - and you'll be able to admire the costumes of Nearly Headless Nick, Moaning Myrtle and the ghost of Slytherin House: the Bloody Baron.
Will there be slimy troll snot? Yup. Three-headed dog drool? Bucket-loads. Unicorn blood? Vials of the stuff. Even better, you'll see how all this monstrous gunk was created for the films.
You'll also get a wand combat lesson, which is just as well, since those who venture down Diagon Alley will find themselves under attack from Lord Voldemort's Death Eaters.