Although its popularity has increased greatly in other countries during the last decades, the Anglo-Saxon countries have centuries of advantage in celebrating Halloween, you just have to take a look at the impressive costume shops that we can find in London to realize how seriously they take it.
Mad World Fancy Dress and Costume Hire: Offers customers a collection of no less than 35.000 costumes, both for sale and for rent. Whatever your idea for Halloween, this store sure has it.
Escapade: This well-known store, located in the neighborhood of Camden, offers its customers a wide range of masks and accessories, as well as complete costumes of characters ranging from the Harry Potter saga to Superman. Ideal for those who prefer to buy a complete costume rather than accessory by accessory.
Prangsta: This shop of costumes It is for those who intend to win the first prize in the contest. It has a great sewing and tailoring service that allows them to make amazing tailored suits, whatever you can imagine.
More information - PortAventura already celebrates Halloween 2013
Source - Time-out